File History problems after installing KB5124008, KB5126052, andKB890830

Question

File History problems after installing KB5124008, KB5126052, andKB890830

BobHayes-3027 35

Ran Windows Update on two sepearate Windows 11 computers that were all up to date as of Saturday morning - broke File History

Today I ran File History on 2 computers - both ran correctly. Then ran Windows Update and File History on both are now broken. File History panel pops up but will not run - says to connect a drive. (drive was connected and verified that I could read and write to it)

Reached out to support who logged on to one of the computers, but troubleshooting did not provide an answer. Later I connected a drive and configured File History on a 3rd computer - it was working. Then I ran Windows Update and it broke it.

Updated the case number and was told now by two seperate techs that it seems to be an issue with one of the updates and was passing it on to level 2 with the detailed testing notes I provided.

The three updates that were installed were

2026-09 Security Update (KB5124008) (26200.9445)

2026-09 .NET Framework Security Update (KB5126052)

Windows Malicious Software Removal Tool x64 - v5.145 (KB890830)

Working before the update - not working after the update

just letting others know in case they are running into the same issue.

Deleted

This comment has been deleted due to a violation of our Code of Conduct. The comment was manually reported or identified through automated detection before action was taken. Please refer to our Code of Conduct for more information.
Alan B 0 Reputation points

2026-09-09T08:30:26.7133333+00:00

I'm having the same issues trying to run my back up to file history on my external drive- failed, same error messages as you. Had to do a manual save to the drive. CHATGPT says likely that what you have highlighted is the problem and microsoft will pick up and solve soon.
La Ma 0 Reputation points

2026-09-10T03:41:21.8066667+00:00

I have just now encountered this same problem. I will try uninstalling the Security Update.
Ezio De Pazzi 126 Reputation points

2026-09-10T05:47:41.74+00:00

exactly what you are expericing.

Answer recommended by moderator

BobHayes-3027 35

Resolved the issue for now by uninstalling
2026-09 Security Update (KB5124008) (26200.9445)

Did this all three computers that had the issue and it resolved the issue on all three.

La Ma 0 Reputation points

2026-09-10T11:03:37.36+00:00

For me also, uninstalling that Security Update resolved the issue. But of course, I also had to pause updates until the end of the month. I don't want Windows Update to re-install it!
BobHayes-3027 35 Reputation points

2026-09-10T11:23:35.6933333+00:00

You can hide the update from being installed so you can still get other updates. Best method I found was using commands in the admin terminal )PowerShell).

Only caveat is that if Windows Update has already downloaded it, you need to install it, uninstall it, then run the commands to block it. Search "Block the Installation of Certain Windows Updates Using PowerShell" on the Internet.
Carl-L 21,480 Reputation points Microsoft External Staff Moderator

2026-09-10T13:44:21.6933333+00:00

Hello BobHayes-3027,

It's good to hear if you have found a way to resolve this.

If you have any other questions. Feel free to ask.
Fred Acosta 0 Reputation points

2026-09-10T15:45:10.5966667+00:00

Thank you BobHayes for posting this. I had the same exact issue and removing KB5124008 resolved it.

Much appreciated.

-Fred A.
Derek S 0 Reputation points

2026-09-10T16:44:35.2+00:00
What concerns me about the "uninstall the update" answer is that it doesn't tell us whether Microsoft has:

acknowledged the bug,

logged it,

reproduced it,

or fixed it.

It merely demonstrates a correlation:

"I removed the update and File History worked again."

That's useful information, but it's not the same as a long-term solution.
BobHayes-3027 35 Reputation points

2026-09-10T17:15:27.69+00:00

Dereck S - I'd like to knw that as well, but as far as I know there is no feedback loop to customers to provide that information. More importantly, will it still be an issue in the next Security Update.

Like youm I'm just a user of Windows sharing the issue and what fixed it for me, and what to be aware of come the next update. I even took the time to install the update - 2026-09 Security Update (KB5124008) (26200.9445) - again on each computer to confirm it was that update that broke File History before uninstalling it to make it work again.

Good Luck
Derek S 0 Reputation points

2026-09-10T18:08:38.93+00:00

Thanks, Bob. I really appreciate you taking the time to post the issue in the first place and then doing the extra testing to confirm the behaviour after reinstalling the update.

Finding your post was actually what prompted me to investigate my own File History setup. Up until then I assumed I was dealing with a problem specific to my PC or backup drive. After working through quite a bit of troubleshooting, I'm now much less convinced that it's simply a hardware issue.

In any case, thank you again for starting the thread and sharing your findings. I'll continue following it with interest and will post back if I discover anything useful.
Derek S 0 Reputation points

2026-09-10T19:07:34.2633333+00:00
I just happened to check Windows Security and Maintenance and discovered that Windows Security and Maintenance is recording repeated crashes of FileHistory.exe:

Problem Event Name: CLR20r3

Faulting application: FileHistory.exe

Module: fhuxadapter

Exception: System.InvalidOperationException

The same crash has been recorded multiple times with the same bucket ID, which suggests a repeatable failure rather than a one-off event.

According to Copilot:

CLR20r3 is a .NET runtime crash. In plain English, it means an application encountered an unhandled exception and terminated unexpectedly.

An InvalidOperationException is essentially:
"The program attempted an operation that wasn't valid for the state it was in."

That's a software exception rather than a hardware error.

The fhuxadapter component is part of the File History user experience/UI layer rather than the actual file-copying engine.

Copilot added:
"That fits surprisingly well with your symptoms:

"Turn Off" does nothing.

"Run now" doesn't actually start a backup.

"Reconnect your drive" appears despite the drive being accessible.

New FileHistory-Engine events aren't appearing.

Those are all UI/control-plane behaviours, not disk I/O failures."
BobHayes-3027 35 Reputation points

2026-09-10T19:51:34.87+00:00

Yes - I showed Tech Support while he was connected to my computer that clicking "Turn Off" did not do anything and clicking "Run Now" only brings up the "Reconnect your drive" message. Also - stopping the FH service, removing the FH folder on your backup drive and "Users\xxxxx\AppData\Local\Microsoft then starting FH does in fact recreate the folders abd allows you to exclude folders and other settings - just won't actually run :)

Hopefully MS will get enough complaints and fix it. What has me a little concerned is that when I reached back out to update them with the info that uninstalling the update fixed the issue they told me that there were no notes under the case number - so I do not have a high level of confidence that it actually went to level 2 for further investigation.
MollFran88 5 Reputation points

2026-09-11T05:53:16.5166667+00:00

As a very unsophisticated older user I really appreciated all the information in this thread, thank you. I uninstalled the security update and could back up onto an external hard drive again. Windows automatically reinstalling the update reproduced the problem. I don't have confidence to pause just one update so will just have to do a few "copy"s of vital files to a different drive every so often until next month. I am concerned though, as I gather the security updates are different each time so that the issues fixed in the suspect update won't be fixed in the following month if I uninstall it.

I don't know how to report it directly to Microsoft, as it looks from the above as if they've not taken anything on board yet.

Thanks guys.

2 additional answers

Your answer

Deleted

This comment has been deleted due to a violation of our Code of Conduct. The comment was manually reported or identified through automated detection before action was taken. Please refer to our Code of Conduct for more information.
Alan B 0 Reputation points

2026-09-09T08:30:26.7133333+00:00

I'm having the same issues trying to run my back up to file history on my external drive- failed, same error messages as you. Had to do a manual save to the drive. CHATGPT says likely that what you have highlighted is the problem and microsoft will pick up and solve soon.
La Ma 0 Reputation points

2026-09-10T03:41:21.8066667+00:00

I have just now encountered this same problem. I will try uninstalling the Security Update.
Ezio De Pazzi 126 Reputation points

2026-09-10T05:47:41.74+00:00

exactly what you are expericing.
La Ma 0 Reputation points

2026-09-10T11:03:37.36+00:00

For me also, uninstalling that Security Update resolved the issue. But of course, I also had to pause updates until the end of the month. I don't want Windows Update to re-install it!
BobHayes-3027 35 Reputation points

2026-09-10T11:23:35.6933333+00:00

You can hide the update from being installed so you can still get other updates. Best method I found was using commands in the admin terminal )PowerShell).

Only caveat is that if Windows Update has already downloaded it, you need to install it, uninstall it, then run the commands to block it. Search "Block the Installation of Certain Windows Updates Using PowerShell" on the Internet.
Carl-L 21,480 Reputation points Microsoft External Staff Moderator

2026-09-10T13:44:21.6933333+00:00

Hello BobHayes-3027,

It's good to hear if you have found a way to resolve this.

If you have any other questions. Feel free to ask.
Fred Acosta 0 Reputation points

2026-09-10T15:45:10.5966667+00:00

Thank you BobHayes for posting this. I had the same exact issue and removing KB5124008 resolved it.

Much appreciated.

-Fred A.
Derek S 0 Reputation points

2026-09-10T16:44:35.2+00:00

What concerns me about the "uninstall the update" answer is that it doesn't tell us whether Microsoft has:

acknowledged the bug,

logged it,

reproduced it,

or fixed it.

It merely demonstrates a correlation:

"I removed the update and File History worked again."

That's useful information, but it's not the same as a long-term solution.
BobHayes-3027 35 Reputation points

2026-09-10T17:15:27.69+00:00

Dereck S - I'd like to knw that as well, but as far as I know there is no feedback loop to customers to provide that information. More importantly, will it still be an issue in the next Security Update.

Like youm I'm just a user of Windows sharing the issue and what fixed it for me, and what to be aware of come the next update. I even took the time to install the update - 2026-09 Security Update (KB5124008) (26200.9445) - again on each computer to confirm it was that update that broke File History before uninstalling it to make it work again.

Good Luck
Derek S 0 Reputation points

2026-09-10T18:08:38.93+00:00

Thanks, Bob. I really appreciate you taking the time to post the issue in the first place and then doing the extra testing to confirm the behaviour after reinstalling the update.

Finding your post was actually what prompted me to investigate my own File History setup. Up until then I assumed I was dealing with a problem specific to my PC or backup drive. After working through quite a bit of troubleshooting, I'm now much less convinced that it's simply a hardware issue.

In any case, thank you again for starting the thread and sharing your findings. I'll continue following it with interest and will post back if I discover anything useful.
Derek S 0 Reputation points

2026-09-10T19:07:34.2633333+00:00

I just happened to check Windows Security and Maintenance and discovered that Windows Security and Maintenance is recording repeated crashes of FileHistory.exe:

Problem Event Name: CLR20r3

Faulting application: FileHistory.exe

Module: fhuxadapter

Exception: System.InvalidOperationException

The same crash has been recorded multiple times with the same bucket ID, which suggests a repeatable failure rather than a one-off event.

According to Copilot:

CLR20r3 is a .NET runtime crash. In plain English, it means an application encountered an unhandled exception and terminated unexpectedly.

An InvalidOperationException is essentially:
"The program attempted an operation that wasn't valid for the state it was in."

That's a software exception rather than a hardware error.

The fhuxadapter component is part of the File History user experience/UI layer rather than the actual file-copying engine.

Copilot added:
"That fits surprisingly well with your symptoms:

"Turn Off" does nothing.

"Run now" doesn't actually start a backup.

"Reconnect your drive" appears despite the drive being accessible.

New FileHistory-Engine events aren't appearing.

Those are all UI/control-plane behaviours, not disk I/O failures."
BobHayes-3027 35 Reputation points

2026-09-10T19:51:34.87+00:00

Yes - I showed Tech Support while he was connected to my computer that clicking "Turn Off" did not do anything and clicking "Run Now" only brings up the "Reconnect your drive" message. Also - stopping the FH service, removing the FH folder on your backup drive and "Users\xxxxx\AppData\Local\Microsoft then starting FH does in fact recreate the folders abd allows you to exclude folders and other settings - just won't actually run :)

Hopefully MS will get enough complaints and fix it. What has me a little concerned is that when I reached back out to update them with the info that uninstalling the update fixed the issue they told me that there were no notes under the case number - so I do not have a high level of confidence that it actually went to level 2 for further investigation.
MollFran88 5 Reputation points

2026-09-11T05:53:16.5166667+00:00

As a very unsophisticated older user I really appreciated all the information in this thread, thank you. I uninstalled the security update and could back up onto an external hard drive again. Windows automatically reinstalling the update reproduced the problem. I don't have confidence to pause just one update so will just have to do a few "copy"s of vital files to a different drive every so often until next month. I am concerned though, as I gather the security updates are different each time so that the issues fixed in the suspect update won't be fixed in the following month if I uninstall it.

I don't know how to report it directly to Microsoft, as it looks from the above as if they've not taken anything on board yet.

Thanks guys.

Answer 1

CrazyKats 19,245 Volunteer Moderator

Hi All,

As of today 26200 is up to .9539.

Hope it fixes the issue for all of you.

BobHayes-3027 35 Reputation points

2026-09-10T20:08:54.9266667+00:00

CrazyKats - Where can I download that to test? I went to teh Microsoft Update Catalog and searched on "KB5124008" - all I see is 23200.9445 - dated 9/8/2026

Thanks
CrazyKats 19,245 Reputation points Volunteer Moderator

2026-09-10T20:13:20.06+00:00

Hi Bob,

Apparently it's a gradual rollout

under Windows Update, so if you don't

see it right away give it a few days.
BobHayes-3027 35 Reputation points

2026-09-10T20:16:06.15+00:00

CrazyKats - thanks - was hoping to be able to install it on one machine to test - guess I will have to wait until it just shows up and then fix all my machines if needed. Oh well.

Answer 2

Carl-L 21,480 Microsoft External Staff Moderator

Hello Bob H,

Welcome to Microsoft Q&A forum.

Before we proceed, may I have a photo of the situation to check for you? Please remember to remove all personal information before posting.

Additionally, may I know if you can rollback the updates?

I'm waiting for your reply.

BobHayes-3027 35 Reputation points

2026-09-09T13:43:43.57+00:00

Sure - here you go - tried it with two external USB drives and one internal drive, all which I have verified can be read and written to. Microsoft Tech support connected to computer and also verified drive was able to be written too as well as doing SFC and DISM commands. Then finally agreed that since File History was working be the updates (manually run prior to installing the updates) and is now not working after the updates on all three computers it is an issue with one or more of the three updates that were installed.

While that error message was being displayed I manually copied a file over to the backup drive and could also read it.

Rather than trying to blindly uninstall all three updates - what order would you suggest I try to uninstall them in?
Derek S 0 Reputation points

2026-09-10T08:34:38.77+00:00

Greetings all,
If I may just add a little more info from my perspective. I am unable to turn File History off! If I click 'Turn off' it still shows that 'File History is on", as in the photo supplied by BobHayes-3027. If I click 'Run now', that's when the message to "Reconnect your drive" appears. I am able to Stop the File History service by running services.msc, but when it is running again, nothing changes from my description above. While trying this last night, it did create the following folder structure on the backup drive: D:\File History<user_name><System_name> which contained two more sub -folders: 'Configuration' and 'Data'. In 'Configuration, there were two files: Config1.xml and Config2.xml but nothing in data. Again, it says it is turned on but if I click Run now, I get the 'reconnect drive' message.
In addition, Copilot is recommending NOT to uninstall KB5124008, with this being an important Security update, so I am reluctant to try that. Also, there is no option to stop using the currently selected drive or the option to select another drive.
Hopefully some of what I've said here may be of use in helping to diagnose this issue. I'm feeling vulnerable now with out File History running.