[SOLVED] Component-Based Servicing (cbs.log) causes all drive space to be consumed

Question

Because I've seen this question asked in many places and not answered, I thought I'd post my issue and resolution here.  I regard this as a Bug, but I'm not invested enough to deal with the support incident process.

I've had repeated instances where a Windows 7 x64 client runs out of hard drive space, and found that C:\Windows\TEMP is being consumed with hundreds of files with names following the pattern "cab_XXXX_X", generally 100 MB each, and these files are constantly generated until the system runs out of space.  Upon removing the files & rebooting, the files start being generated again.

I've found that this is caused by large Component-Based Servicing logs.  These are stored at C:\Windows\Logs\CBS.  The current log file is named "cbs.log".  When "cbs.log" reaches a certain size, a cleanup process renames the log to "CbsPersist_YYYYMMDDHHMMSS.log" and then attempts to compress it into a .cab file.

However, when the cbs.log reaches a size of 2 GB before that cleanup process compresses it, the file is to large to be handled by the makecab.exe utility.  The log file is renamed to CbsPersist_date_time.log, but when the makecab process attempts to compress it the process fails (but only after consuming some 100 MB under \Windows\Temp).  After this, the cleanup process runs repeatedly (approx every 20 minutes in my experience).  The process fails every time, and also consumes a new ~ 100 MB in \Windows\Temp before dying.  This is repeated until the system runs out of drive space.

This can be reproduced by trying to manually create the cab file -

 Directory of C:\CBS-BAK

08/26/2015  02:28 PM    <DIR>          .

08/26/2015  02:28 PM    <DIR>          ..

08/22/2015  09:12 PM     2,491,665,966 CbsPersist_20150823021618.log

C:\CBS-BAK>makecab CbsPersist_20150823021618.log

Cabinet Maker - Lossless Data Compression Tool

 86.19% - CbsPersist_20150823021618.log (1 of 1)

ERROR: (FCIAddFile)Data-size or file-count exceeded CAB format limits

C:\CBS-BAK>dir %TEMP%\cab*

 Volume in drive C is OSDisk

 Volume Serial Number is 44DE-0CDD

 Directory of C:\Users\USERNAME\AppData\Local\Temp

08/26/2015  02:31 PM       102,786,654 cab_4556_2

08/26/2015  02:28 PM                 0 cab_4556_3

08/26/2015  02:28 PM                 0 cab_4556_4

08/26/2015  02:28 PM                 0 cab_4556_5

08/26/2015  02:28 PM                 0 cab_4556_6

08/26/2015  02:28 PM        12,978,919 cab_5860_2

08/26/2015  02:27 PM                 0 cab_5860_3

08/26/2015  02:27 PM                 0 cab_5860_4

08/26/2015  02:27 PM                 0 cab_5860_5

08/26/2015  02:27 PM                 0 cab_5860_6

To resolve this -

Stop the Windows Modules Installer (TrustedInstaller) service

Delete or move the large Cbspersist_XX.log file out of \Windows\Logs\CBS.

Start the Windows Modules Installer (TrustedInstaller) service

Answer 1

Answer

Thanks to this other post I was able to get my system straight. Hopefully you can find the same.

CA

CautiousPanda replied on

I posted this somewhere else but it sorta got drowned out by the way this forum works.

TLDR; Settings > Update > Advanced Options > Pause Updates > on > Hard reset > Install update manually from catalogue > Unpause after updater reset.

This is what worked for me when '2017-12 Cumulative Update for Windows 10 Version 1709 for x64-based Systems (KB4054517)' was not installing, even manually:

1. Start.
2. Settings.
3. Update & Security.
4. Windows Update > Scroll under the 'Update Settings' click > 'Advanced Options'.
5. Advanced Options > Scroll under 'Pause Updates' click the slide button to 'on' to pause the update. If its not there scroll down this post to see an alternative to this step.
6. Make sure nothing is writing to your storage and then force shutdown your computer by holding the hardware/physical power button down, then turn your computer back on. NOTE: Step 5 is what fixed manually updating for me. Other methods that official Microsoft posters have suggested may work properly from this step on but the following is what I did.
7. When it starts back up, install the update manually from the Microsoft update catalogue. https://www.catalog.update.microsoft.com. Search: KB4054517 or the one you want. Then click the download button on the right for your version and run the link that pops up after.
8. It should do its slow, updating restart but actually work now because of step 5.
9. Turn the pause updates off so things work normally and remember this process if the same issue occurs in the future. Hopefully it does work normally in the future though.
10. If it doesn't work maybe try below instead of step 5

If Pause Updates isn't there

Do this instead of step 5

1. Open the Run command (Win + R), in it type: services.msc and press enter
2. From the Services list find the Windows Update service
3. Right click > properties > startup type > disabled > apply
4. Hard Restart, go back to step 6
5. When you get to step 9 set this service back to Automatic.

Extra:

I had hangs at 99%, I used the troubleshooter, I used the update assistant, I had the updater download the same failing update file repeatedly in the background without deleting the one that wasn't working until nearly all 110GB of my SSD was filled up, I had a bunch of error codes (don't remember which ones though), I reset/refreshed/reinstalled the Windows 10 install 3 times with no solution in sight. I was at this for 3 days.

The clue for my issue:

The Microsoft update catalogue download of the update failed saying "the following update was NOT installed" (pointing to itself) and the update troubleshooter said that there was a 'pending restart' so it could not help. Which is what lead me to pause the updates because that would turn off the pending restart. If that was making the update troubleshooter not work, maybe that was also making the manual update not work. I think that turned out to be the issue, for my case.

Someone on this thread did some more digging into why this happens I don't understand it but here: https://answers.microsoft.com/en-us/windows/forum/windows_10-update/windows-10-cumulative-update-kb4054517-fails-to/5bde0909-3d46-4725-8681-d5d500780963

Answer 2

Start and Stop are greyed out when I access the Windows Modules Installer through services.msc. What now? Accessing as Administrator made no difference.

Answer 3

Thank you. I will give this a shot!