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[Q] possible soft brick nexus s

I have here is a Nexus S with the MUI Rom. The Rom was working for a couple of days until I ran out of battery. When I plug the charging cable, the phone powers on and shows the boot logo and then the google screen. I can't get pass the google screen or go into clockmod's recovery.

panguinx said:
I have here is a Nexus S with the MUI Rom. The Rom was working for a couple of days until I ran out of battery. When I plug the charging cable, the phone powers on and shows the boot logo and then the google screen. I can't get pass the google screen or go into clockmod's recovery.
Click to expand...
Click to collapse
Have you tried reflashing recovery via fastboot? If you see the Google logo it's trying to boot.
Reflash recovery via fastboot and reflash your rom of choice.

krohnjw said:
Have you tried reflashing recovery via fastboot? If you see the Google logo it's trying to boot.
Reflash recovery via fastboot and reflash your rom of choice.
Click to expand...
Click to collapse
I'd tried and didn't work either, but i was able to get to the bootloader screen. I can't get my computer to see the phone while its in the bootloader screen.

Maybe you could boot into recovery from the bootloader and use a nandroid backup of some sort?

mathkid95 said:
Maybe you could boot into recovery from the bootloader and use a nandroid backup of some sort?
Click to expand...
Click to collapse
I can't get into recovery from bootloader, when I click on recovery, it looks like it's going to boot but nothing happen. I leave the phone on over night and nothing happen.

Ah...no worries..
stay in ur bootloader.
download a clockworkmod recovery image and cd into the directory u r in.
Perform the following commands if you ALREADY have a recovery img installed:
1. fastboot erase recovery
2. fastboot flash recovery _____.img (the blank line is the recovery img name)
3. reboot into recovery and perform ur nandroid
If you DON'T have a recovery img installed, then skip step 1

mathkid95 said:
ah...no worries..
Stay in ur bootloader.
Download a clockworkmod recovery image and cd into the directory u r in.
Perform the following commands if you already have a recovery img installed:
1. Fastboot erase recovery
2. Fastboot flash recovery _____.img (the blank line is the recovery img name)
3. Reboot into recovery and perform ur nandroid
if you don't have a recovery img installed, then skip step 1
Click to expand...
Click to collapse
omg omg omg omg double rainbow it work, you are the master of rooting!!!!!!!!!!!!!!!!!!!!!!!!! I would like to send you a thank you card if i can.
Thanks much

Haha yay! Glad I could help!

mathkid95 said:
Haha yay! Glad I could help!
Click to expand...
Click to collapse
haha step 1 is a bit senseless!
and next time try fastboot erase data
Sent from my Nexus S using XDA Premium App

No I was assuming he HAD recovery image installed...so erase it because he couldnt boot into it...might have been a bad recovery img

Please help me Please help me Please help me Please help me Please help me Please help me Please help me Please help me Please help me Please help me Please help me Please help me Please help me Please help me Please help me
HELLO FRIENDS
FIRST let me say this,
The mother-tongue is not English. Know a bit. GT-S MY NEXUS İ9023 phone. PHONE HAS BRICK. 4 Touch ON KEY ONLY occasionally. DO NOT LIKE ANY IMAGE. HOW TO BECOME BECAUSE OF MY BRICK i900 ROM. DO NOT VIEW ANY PHONE. THE FOLLOWING AS in the video. (VIDEO NOT FOR MY PHONE).
.youtube.com/watch?v=AyzIYBq0ODw
It PHONE BUT LIKE opening in the direction (in the background). POWER BUTTON PHONE IN NORMAL PRESSURE shaking 30-35 seconds after the button and the SOUND ON SOUND COMING DIT DIT. I want to ask YOU WANT TO 301K application of the technique. Should I continue using THIS EVENT. Looking forward to GREAT ANSWERS
Please help me Please help me Please help me Please help me Please help me Please help me Please help me Please help me Please help me Please help me Please help me Please help me Please help me Please help me Please help me

Soft Brick..no USB to help
Nexus S 4g is not connecting to the mobile network. Because of this I am trying to go back to the Sprint stock firmware. USB is properly charging my phone, but I'm unable to have the device enumerated by my pc. I've tried multiple cables, OS's, and PCs. USB is not enumerated even in the bootload state.
I have reverted to a backup when everything was working, but I still have the same problem with the network and USB.
WiFi works so getting new firmwares from ClockworkMod is an option, but going to CM7 did not resolve the problem.
I've read the forums and not found any solution yet. Has anyone heard of this before? Are there any options I can still try through software?

mathkid95 said:
Ah...no worries..
stay in ur bootloader.
download a clockworkmod recovery image and cd into the directory u r in.
Perform the following commands if you ALREADY have a recovery img installed:
1. fastboot erase recovery
2. fastboot flash recovery _____.img (the blank line is the recovery img name)
3. reboot into recovery and perform ur nandroid
If you DON'T have a recovery img installed, then skip step 1
Click to expand...
Click to collapse
I want to try this on my brick nexus. The img must be on nexus s?
The commands is on a linux?

trentontrees said:
Nexus S 4g is not connecting to the mobile network. Because of this I am trying to go back to the Sprint stock firmware. USB is properly charging my phone, but I'm unable to have the device enumerated by my pc. I've tried multiple cables, OS's, and PCs. USB is not enumerated even in the bootload state.
I have reverted to a backup when everything was working, but I still have the same problem with the network and USB.
WiFi works so getting new firmwares from ClockworkMod is an option, but going to CM7 did not resolve the problem.
I've read the forums and not found any solution yet. Has anyone heard of this before? Are there any options I can still try through software?
Click to expand...
Click to collapse
Did you get this figured out? I'm having the same problem.

trentontrees said:
Nexus S 4g is not connecting to the mobile network. Because of this I am trying to go back to the Sprint stock firmware. USB is properly charging my phone, but I'm unable to have the device enumerated by my pc. I've tried multiple cables, OS's, and PCs. USB is not enumerated even in the bootload state.
I have reverted to a backup when everything was working, but I still have the same problem with the network and USB.
WiFi works so getting new firmwares from ClockworkMod is an option, but going to CM7 did not resolve the problem.
I've read the forums and not found any solution yet. Has anyone heard of this before? Are there any options I can still try through software?
Click to expand...
Click to collapse
Please connect it (in bootloader/fastboot and/or recovery mode) to a Linux PC. Then post the output of commands:
Code:
tail /var/log/messages
Code:
lsusb

[Q] Nexus s stuck on Google Screen

My Nexus s i9020T is stuck on the google screen. I was trying to root it and when it was done my phone rebooted and it got stuck on the google screen. My bootloader is unlocked and i was running on gingerbread 2.3.6 can somebody tell me how to resolve this issue using a mac

How long did you waited? Sometimes that Google logo could tale a long time. Try going through the root process again
Sent from my Nexus S using Tapatalk 2

Same problem
I got the same problem. i can access recovery mode but my phone is not getting detected in PC. just hangs on Google logo (white) :crying:
bootloader os locked also.
My Model is GT-I9020T.
please help.
thanks in advance.

You should try the usb jig sold on ebay for the Nexus S.. It will bring the phone to download mode so you can flash your firmware with odin.. To use odin on your mac you need to have Windows installed with a virtual machine or virtualbox..
---------- Post added at 03:40 AM ---------- Previous post was at 03:35 AM ----------
Kumar Anil said:
I got the same problem. i can access recovery mode but my phone is not getting detected in PC. just hangs on Google logo (white) :crying:
bootloader os locked also.
My Model is GT-I9020T.
please help.
thanks in advance.
Click to expand...
Click to collapse
Bad luck for you.. Since your bootloader is locked and you can't unlock it you can't do anything.. Also you are talking about stock Android recovery right..? No TWRP or CWM..?

same problem
thanks for replying.
actually
I have google nexus GT-I9020t. it hangs on google logo (white). fastboot oem unlock is not working. lock state : locked.
when i go into recovery mode and try to wipe data/factory reset, it says:
e:format_volume: make_extf4fs failed on /dev/block/platform/s3c-sdhc1.0/byname/userdata
if i try to flash using fastboot, it says run fastboot oem unlock command.
it is not detecting in odin also. i have installed the drivers though.
else it is going to recovery mode, showing the lock status and i can also go futher in format, data wipe menu.
anything i can purchase will help or not, i dont know.
please help.

Kumar Anil said:
thanks for replying.
actually
I have google nexus GT-I9020t. it hangs on google logo (white). fastboot oem unlock is not working. lock state : locked.
when i go into recovery mode and try to wipe data/factory reset, it says:
e:format_volume: make_extf4fs failed on /dev/block/platform/s3c-sdhc1.0/byname/userdata
if i try to flash using fastboot, it says run fastboot oem unlock command.
it is not detecting in odin also. i have installed the drivers though.
else it is going to recovery mode, showing the lock status and i can also go futher in format, data wipe menu.
anything i can purchase will help or not, i dont know.
please help.
Click to expand...
Click to collapse
I made a USB JIG And its showing me some screen. please Check and update.

Kumar Anil said:
I made a USB JIG And its showing me some screen. please Check and update.
Click to expand...
Click to collapse
I remember this screen when I first rooted my Nexus S GTi9023. About the Google logo keep showing, phone probably not finding correct bootloader. I have this issue when I tried jellyBam rom. Fortunalty I had the nandroid back up of other roms that I have tried and I pick up then CM 10.1.2 and choose its backup file for restoring bootloader. Here you me also flash bootloader from PC as well as.

vikaskanani said:
I remember this screen when I first rooted my Nexus S GTi9023. About the Google logo keep showing, phone probably not finding correct bootloader. I have this issue when I tried jellyBam rom. Fortunalty I had the nandroid back up of other roms that I have tried and I pick up then CM 10.1.2 and choose its backup file for restoring bootloader. Here you me also flash bootloader from PC as well as.
Click to expand...
Click to collapse
But how to flash a bootloader? when i try "fastboot oem unlock" it fails. and when it is locked i cant flash a bootloader. any suggestions?

Kumar Anil said:
But how to flash a bootloader? when i try "fastboot oem unlock" it fails. and when it is locked i cant flash a bootloader. any suggestions?
Click to expand...
Click to collapse
You need to accept the warning message, the screen you attached.
Have a look at redmondpie.com/unlock-nexus-s-bootloader-how-to-guide/ (sorry cant post link as i am new user)
As I said, its been a long time, since I rooted, so I guess, you need to use power key or volume key for any action.

fastboot oem unlock not working
vikaskanani said:
You need to accept the warning message, the screen you attached.
Have a look at redmondpie.com/unlock-nexus-s-bootloader-how-to-guide/ (sorry cant post link as i am new user)
As I said, its been a long time, since I rooted, so I guess, you need to use power key or volume key for any action.
Click to expand...
Click to collapse
I guess, USB debugging mode was not checked at the time of the crash. It is detecting in the fastboot devices command but not in ADB devices.
i did everything in the link, you provided me.
and any other way to force partion of somthing. Any Other Option.
FATSBOOT OEM COMMAND:
http://s10.postimg.org/r0rjcrxe1/fastboot_oem_failed.jpg
thanks in advance

Can you boot in jelly bean?? Strange issue!
Sent from my Nexus 7 using xda app-developers app

[Q] Latest root method for 4.1.1?

I just picked this up for a back up phone and looking for the latest way to root this version.
I've noticed a few one clicks and some others using SDK but a lot of these seem to be old threads that have not been updated for this version. I need someone's help in pointing to the right tutorial for 4.1.1 stock NS4G.
I'm using the one-click-8.0 and Sabra's but every time I click 'Locked' it brings me to the Bootloader screen and I do not know what to click after that.

nyczwillz said:
I just picked this up for a back up phone and looking for the latest way to root this version.
I've noticed a few one clicks and some others using SDK but a lot of these seem to be old threads that have not been updated for this version. I need someone's help in pointing to the right tutorial for 4.1.1 stock NS4G.
I'm using the one-click-8.0 and Sabra's but every time I click 'Locked' it brings me to the Bootloader screen and I do not know what to click after that.
Click to expand...
Click to collapse
Stop using 1 click crap. Rooting a Nexus S takes 10 minutes at best. Nothing changed since the phone came out because it's a piece of cake to unlock a Nexus S, heck, it's meant to be unlocked.
Download and install ADB drivers
Download and unpack fastboot & adb
Connect your phone to your PC. Reboot in bootloader mode (VOL UP and PWR)
From a command line, fastboot oem unlock
On your phone, scroll to Yes, press pwr
This will wipe your phone
Reboot to bootloader again, flash a custom recovery (fastboot recovery recovery.img)
Reboot to recovery (VOL UP and PWR, then scroll then recovery and press pwr)
From within, flash su or supersu.
Tada! Just rooted your phone.
Edit: Here's a link to a guide with pictures and every necessary file linked.
http://digitalpbk.com/nexus-s/how-to-root-nexus-s-windows
I recommend using a more up to date recovery though, and flashing it instead of simply booting from it.

this worked for me above anything else:
http://www.wugfresh.com/dev/nexus-root-toolkit/

[Q] Stuck in "FASTBOOT MODE - NO BOOT OR RECOVERY IMG"

My NExus S is stuck on the screen that says:
Fastboot Mode No Boot or Recovery IMg.
Product Name - Herring
HW Version - Rev34
Bootloader Version - D720SPRKC5
Baseband Version - D720SPRLCI
Carrier Inro - SPR
Serial Number 32300E25C33500EC
Lock State - Locked
options to select
Reboot Bootloader (gives me exact same screen) except it only says "Fastboot"
Reboot Back to the "FASTBOOT MODE - NO BOOT OR RECOVERY IMG"
Recovery (Can boot to CWM but I can't mount anything)
Power OFF (That works fine)
Then the little green man and the android logo
Followed by USB Control INIT
USB Control INIT End
STANDARD_SET_CONFIGURATION
Conventional wisdom says download some files and fix via fastboot. However in fastbootI can't run ANY of the steps without running FASTBOOT OEM UNLOCK. When I run it my phone asks if I really want to unlock the bootloader. when I choose YEs and hit power it just freezes there.
My next thought Boot to recovery and restore. A restore through recovery followed by a reboot leads me back to the original no boot or recovery img.
Okay I'll just sideload a working rom by mounting usb storage. Then I can flash it with CWM and be up and running.
but when I try to do mount the USB Storage I get "E:Unable to write to ums 1unfile (No such file or directory)"
Finally, Last ditch Effort, I'll load up ODIN and use that to put on a working recovery. there's forums all over the place explaining how to do that right? Well yes, but the links to the Tar file are all broken.
What next my friends? I'd really like to get this phone working.

Wug's Nexus Root Toolkit.

ej8989 said:
Wug's Nexus Root Toolkit.
Click to expand...
Click to collapse
I tried doing the Flash stock + unroot in wug's kit but no luc. any other ideas?

swing4thefence said:
I tried doing the Flash stock + unroot in wug's kit but no luc. any other ideas?
Click to expand...
Click to collapse
Your bootloader is LOCKED. You must first UNLOCK the bootloader by clicking "Unlock" on Nexus Root Toolkit.

ej8989 said:
Your bootloader is LOCKED. You must first UNLOCK the bootloader by clicking "Unlock" on Nexus Root Toolkit.
Click to expand...
Click to collapse
No matter how I try to do it, it always freezes at the unlock bootloader step.

Did you install proper drivers?

ej8989 said:
Did you install proper drivers?
Click to expand...
Click to collapse
I thought so. My wife is on the computer so if she ever gives it back I'll re-install the drivers and try again.

swing4thefence said:
I thought so. My wife is on the computer so if she ever gives it back I'll re-install the drivers and try again.
Click to expand...
Click to collapse
Reinstalled Drivers. Still no luck.

I have the same problem.

Same situation for me, because i pressed "Reboot" in CWM without having flashed a Rom (stupid ). Broken power button, hanging on Google logo or in Fastboot mode.
I hope RTK will help me :good: :laugh:
Edit: I have no idea how to revive my Nexus S. Status: Broken Power button, Bootloop, can access Fastbood Mode but dont select someting, Bootloader unlocked, RTK doesn´t find any devices in Fastboot Mode, Device is rooted and has CWM

!Lür said:
Same situation for me, because i pressed "Reboot" in CWM without having flashed a Rom (stupid ). Broken power button, hanging on Google logo or in Fastboot mode.
I hope RTK will help me :good: :laugh:
Edit: I have no idea how to revive my Nexus S. Status: Broken Power button, Bootloop, can access Fastbood Mode but dont select someting, Bootloader unlocked, RTK doesn´t find any devices in Fastboot Mode, Device is rooted and has CWM
Click to expand...
Click to collapse
what about just using adb? Can you find it when you type fastboot devices? If so there's a command in fastboot to reboot to recovery I think.
I on the other hand am screwed. I read in another forum that it hangs on unlock because the internal memory is fubar.

swing4thefence said:
what about just using adb? Can you find it when you type fastboot devices? If so there's a command in fastboot to reboot to recovery I think.
I on the other hand am screwed. I read in another forum that it hangs on unlock because the internal memory is fubar.
Click to expand...
Click to collapse
Solution for me:
1. Turn device on into Bootloop
2. Connect it via USB (PC founds it)
3. type in CMD "adb reboot recovery"
4. device is in recovery
5. reflash everything i wanted :good:
Requirement is a working Android-SDK!

I wish it was that easy for me. I can access recovery just fine. It's the memory I can't touch. Unless someone knows a way to fix corrupted memory...
Sent from my SCH-I510 using xda app-developers app

Im having this same issue too i can still get to CWM recovery but nothing really helps from there. I can still mount my storage and put zip files on there etc but nothing seems to fix the problem...any progress?

swing4thefence said:
I wish it was that easy for me. I can access recovery just fine. It's the memory I can't touch. Unless someone knows a way to fix corrupted memory...
Sent from my SCH-I510 using xda app-developers app
Click to expand...
Click to collapse
I think I'm going to try using my computer to mount and format the internal memory. any ideas as to the correct settings to use when I try this? at this point what have I got to lose?

swing4thefence said:
I think I'm going to try using my computer to mount and format the internal memory. any ideas as to the correct settings to use when I try this? at this point what have I got to lose?
Click to expand...
Click to collapse
Was this solved by any means ??, i am myself stuck at that position

Flash the stock image again using the Nexus Toolkit
Sent from my Nexus S using xda app-developers app

Akbar89 said:
Flash the stock image again using the Nexus Toolkit
Sent from my Nexus S using xda app-developers app
Click to expand...
Click to collapse
Wug's Nexus toolkit ?? It is stuck on bootloader unlock menu, as unlocking bootloader makes it freeze. Without unlock it doesn't flashI anything.
If there is another tool please guide me with link.
Avoid Spells!!! "Auto correct : ON"

stuck on fastboot mode(lenovo S860)
recently i've bought lenovo s860 (2GB version).....its latest updates had bugs....so i was trying to downgrade to lower version(jelly bean).....in the way i got stuck in fastboot mode......is there any way to get out of it??

same problem in galaxy nexus i9250m
ej8989 said:
Did you install proper drivers?
Click to expand...
Click to collapse
i have same problem in galaxy nexus i9250m
my bootloader showingh no boot or recovery img
i have working fastboot, workin adb and driver
my oem is unlocked with fastboot
bt i am unable to flash recovery and rom

Rooting new nexus 5 with 6.01

Android 6.0.1, build number MOB30H
I have a brand new nexus 5 that I want to root. Using ota, I accepted the system updates to 6.0.1 with the Android security patch of May 1, 2016. (not sure if that was a good idea or not but it's done now....). Now I want to root it with a twrp recovery.
Like most run of the mill users I've only rooted a device 2-3 times in my life, so my memory is rusty on how exactly to do it. I searched this forum and found many threads about this or that rooting problem which just confused me further. I know I need to unlock the bootloader and then flash a twrp recovery but I am not sure of the exact sequence of steps.
1. When I connect the nexus 5 to my windows pc using adb, it appears in Windows but the nexus 5 folder is empty. I have developer options available and usb debugging is on but I can't find where the mtp switch is.
2. Adb.
I have adb installed in Windows. The command "adb devices" returns the nexus 5 number unauthorized.
Don't know what "unauthorized" means or what to do about it.
I've done nothing further because I don't want to mess things up. Please help me resolve questions 1 and 2. Then, I presume I need to
A. unlock the bootloader
Fastboot command?
B. What's next?
Thanks for any help.

Two things, have you enabled developer options. Go to settings, about phone and tap build number 7 times. In developer options you can change USB configuration and you'll also need to enable OEM unlock. Then unlock and root your device per the guide in the general section.
Sent from my Nexus 9 using XDA Free mobile app

jd1639 said:
Two things, have you enabled developer options. Go to settings, about phone and tap build number 7 times. In developer options you can change USB configuration and you'll also need to enable OEM unlock. Then unlock and root your device per the guide in the general section.
Click to expand...
Click to collapse
Just to add,not to confuse him even more, there is no Oem unlock option for Nexus 5
Sent from my Alps Q10101 using XDA Labs

You need to connect the phone in fastboot mode, run the command "fastboot oem unlock:, accept the agreement using the volume and power buttons, reboot into fastboot mode, flash twrp, copy the latest version of supersu.zip to the phone's internal memory, and flash supersu.zip from twrp.
You can install TWRP and root without using ADB commands.

Yes I already had developer options working and also usb debug on.
Discovered that mtp is a problem in marshmallow. I finally got file transfer working.

audit13 said:
You need to connect the phone in fastboot mode, run the command "fastboot oem unlock:, accept the agreement using the volume and power buttons, reboot into fastboot mode, flash twrp, copy the latest version of supersu.zip to the phone's internal memory, and flash supersu.zip from twrp.
You can install TWRP and root without using ADB commands.
Click to expand...
Click to collapse
Thank you very much. That is very helpful.
I didn't know you could "install TWRP and root without using ADB commands". How do you do that?
BTW, I updated the new nexus 5 to marshmallow inadvertently. When I root I'll probably use a 5.1.1 image. Good idea?

Stevica Smederevac said:
Just to add,not to confuse him even more, there is no Oem unlock option for Nexus 5
Sent from my Alps Q10101 using XDA Labs
Click to expand...
Click to collapse
Yep, my bad. Sorry about that. My 5 crapped out and have the 5x now. Amazing how fast you forget things, lol.
Sent from my Nexus 9 using XDA Free mobile app

Download and flash twrp in fastboot mode: https://dl.twrp.me/hammerhead/twrp-3.0.2-0-hammerhead.img.html
Download supersu.zip and save it to the phone's internal memory: https://download.chainfire.eu/921/SuperSU/UPDATE-SuperSU-v2.65-20151226141550.zip
Boot the phone into fasboot mode, open a command prompt, type fastboot devices and press enter. If the device is recognized, you'll see the device's serial number. Unlock the bootloader by typing "fastboot oem unlock" and use the volume/power button to accept the agreement and unlock the bootloader. Unlocking the bootloader will wipe the phone's data and cache.
To install TWRP, boot the phone into fastboot mode, connect it to the computer, open a command prompt, and type "fastboot flash recovery name-of-TWRP-file,img" and press enter. After flashing, immediately boot into recovery using the power and volume buttons, and then flash supersu.zip.

Thank you so much audit13. I really appreciate your help.
One question if I may. Reading on the web about rooting the nexus 5 running marshmallow I came across a couple of sites that said I should download and flash "ElementalX kernel and SuperSU 2.52" in addition to supersu.
I've never had to install a separate kernel when I rooted in the past. I notice you don't add flashing a kernel either. Can I ignore flashing a special kernel?
Thank you so very much for your clear instructions.

Some root methods require a rootable kernel. The latest supersu should root mm.

Thank you. Ran into a problem. That's why people like me are afraid of rooting.
Bootloader is now unlocked. Thanks.
With the N5 in fastboot mode, I connected it again with the laptop.
From the laptop command prompt I ussued "fastboot devices" and it found the phone.
Problem:
1. Fastboot flash recovery.img
(I had renamed the twrp 3.0.2 img file to recovery. Img)
Result:
unknown partition 'recovery.img'
error: cannot determine image filename for' recovery.img'
Tried by downloading a fresh copy and using its original filename.
Same result.
What am I doing wrong?
Thank you.

Found my error. I forgot the word recovery.
I now flashed twrp successfully!
When I went to flash supersu I discovered that the supersu I had downloaded was no longer in download folder. Guess it got wiped. So I rebooted into system and will download it again. Hope that does not mess up things.
Edit:
All went well. Re-downloaded SuperSU, installed fine and I'm home free.
Thank you all, especially audit13. This is a nerve-wracking process for people who only do it rarely. Glad it is over. The rest is easy!

I spoke too soon. I believe I now have a boot loop? What I have is that the horizontal turning balls of marshmallow go around forever and never finish booting.
How do I exit from this?
So close, but not there!
Edit
I rebooted into twrp, deleted cache, davlik. Still in bootloop.
Deleted data. Still in bootloop.
Help.

Reflash the entire stock rom and start over.
Try the latest beta of supersu: http://forum.xda-developers.com/apps/supersu/2014-09-02-supersu-v2-05-t2868133

Great you are still here.
Need more details.
You say reflash stock rom. Where do I get it? How do I get it into the phone? Do I flash it through twrp?

How to flash factory image: http://forum.xda-developers.com/google-nexus-5/general/tutorial-how-to-flash-factory-image-t2513701
Factory images are here: https://developers.google.com/android/nexus/ota#hammerhead

Thank you again. Will do.
I think I know what went wrong. After I flashed twrp the phone rebooted into system before I could stop it and I think I interrupted it somewhere to return to twrp to flash Supersu. Anyway, glad I didn't brick it. Thanks again for being there.
It's morning now and after a good night's sleep I'm less rattled. Will get breakfast and start again.

I'm going out with my wife for breakfast.
I haven't followed the marshmallow threads but I recall reading about lingering problems with marshmallow. I also like to use xprivacy and gravitybox. So I'm thinking of flashing the latest 5.1.1 instead of 6. Any thoughts?

I like both ROMs but my battery life seems a bit better on MM. I'm sticking with unrooted stock ROMs on all of my phones for now.
Being a "flashaholic" is tiring!

audit13, I know you know this but it was so simple to do (once you know how.....!). It took me the whole of 20 minutes, if that, to download the files, flash 5.1.1, flash twrp and install SuperSU. Makes you wonder why I had so much trouble before!
Well when you don't know the command syntax (forget to write which partition to flash to) and are frozen with fear that you will brick the phone, it is a scary process. Once I knew how, I breezed through it. Problem is that by the next time I need to do this, I will have forgotten how or will worry that the process has changed.
I just want to thank you more than I can say for helping and hanging in while I made my mistakes. I wish there was a way I could thank you with more than words. You were great!
P.S. This time I used the beta SuperSU. Don't know if it made any difference.