Class outlook is not working properly after Windows 11 version 25H2 update

Question

Class outlook is not working properly after Windows 11 version 25H2 update

Joe E 10

Windows 11 version 25H2 updated was automatically updated on Feb 17, 2026. Ever since this, the functions on my classic outlook email are no longer working - none of the functions in the ribbon for email are working - e.g. cannot send a new email, cannot send/receive and also cannot open/close email. This occurred right after the update to Windows 11 25H2 which was installed automatically.

Please help as I also cannot uninstall the Windows 11 25H2 update.

Hornblower409 7,110 Reputation points

2026-02-20T22:29:16.6766667+00:00

@Joe E
If the Q&A Assist Answer did not solve your problem:

Click the "Reject" button at the bottom of the Q&A Assist Answer. This should signal the forum moderators that you still need help and a human should reply within a day or two.

Or type "Not Solved" in the "Add Comment" box and click the [Add Comment] button, and I will try to offer some suggestions on what you can do next.
Teresa Hincky 0 Reputation points

2026-02-22T04:58:15.13+00:00

I also have this problem. Can you provide me with details of the set up changes that you had to make?
Joe E 10 Reputation points

2026-02-23T14:53:30.7433333+00:00

I contacted Microsoft Support. I have 2 email accounts. One of the accounts, a hotmail.com account was causing problems, I don't know exactly why, however by deleting this account which I don't use much anyway, the ribbon in my outlook email is working again.

Hope this helps.

Answer recommended by moderator

0 additional answers

Your answer

Hornblower409 7,110 Reputation points

2026-02-20T22:29:16.6766667+00:00

@Joe E
If the Q&A Assist Answer did not solve your problem:

Click the "Reject" button at the bottom of the Q&A Assist Answer. This should signal the forum moderators that you still need help and a human should reply within a day or two.

Or type "Not Solved" in the "Add Comment" box and click the [Add Comment] button, and I will try to offer some suggestions on what you can do next.
Teresa Hincky 0 Reputation points

2026-02-22T04:58:15.13+00:00

I also have this problem. Can you provide me with details of the set up changes that you had to make?
Joe E 10 Reputation points

2026-02-23T14:53:30.7433333+00:00

I contacted Microsoft Support. I have 2 email accounts. One of the accounts, a hotmail.com account was causing problems, I don't know exactly why, however by deleting this account which I don't use much anyway, the ribbon in my outlook email is working again.

Hope this helps.

Answer 1

Joe E 10

I received support from a Microsoft agent . Problem has been solved by addressing email set up.

thanks

Jim Wilson 5 Reputation points

2026-02-23T13:34:42.2433333+00:00

Not enough information. Did you have to run Office Repair or change the configuration elsewhere?
Joe E 10 Reputation points

2026-02-23T14:55:08.03+00:00

I contacted Microsoft Support. I have 2 email accounts. One of the accounts, a hotmail.com account was causing problems, I don't know exactly why, however by deleting this account which I don't use much anyway, the ribbon in my outlook email is working again.

Hope this helps.
Jim Wilson 5 Reputation points

2026-02-23T15:13:49.86+00:00

As a possible remedy for others, I'm going to say it is most likely caused by PST files (used by non-Exchange accounts) stored in "Documents/Outlook Files" that are being synchronized by OneDrive as the root issue. The recommendation is to move any and all PST files to a local directory such as C:\PST (or something like that) which is not synchronized with OneDrive.

It has long been the recommendation that OneDrive should not synchronize multi-GB or database files that would be better off in a local folder due to frequent updates in such files.
Hornblower409 7,110 Reputation points

2026-02-23T19:54:44.1833333+00:00

@Jim Wilson said

caused by PST files (used by non-Exchange accounts) stored in Documents/Outlook Files" that are being synchronized by OneDrive

This was certainly the case with the problems caused by KB5074109 in Jan 2026. But that was fixed by subsequent updates.

https://support.microsoft.com/en-us/office/classic-outlook-profiles-with-pop-accounts-and-psts-hang-after-windows-updates-on-january-13-2026-590fe356-ecc2-49f4-b9e3-bd39fafa58f6

https://support.microsoft.com/en-us/topic/january-24-2026-kb5078127-os-builds-26200-7628-and-26100-7628-out-of-band-cf5777f6-bb4e-4adb-b9cd-2b64df577491

recommendation that OneDrive should not synchronize multi-GB or database files that would be better off in a local folder due to frequent updates in such files

I agree. And I personally do not keep any of my Outlook Data Files in my OneDrive Folder.

But, as you can see from some of the comments on the KB5074109 problem

https://learn.microsoft.com/en-us/answers/questions/5707915/outlook-classic-not-opening-properly-or-recording

For many people, OneDrive is their only form of backup and they were, understandably, reluctant to give that up.
Jim Wilson 5 Reputation points

2026-02-23T21:28:21.9366667+00:00

Sorry, I contend subsequent updates did not correct the issue with KB5074109. We show KB5078127 was installed on 1/13/2026 as well as the superseding update KB5077181 on 2/10/2026 as a result of Group Policies for Windows Update which mandate daily checking and installation of available updates and a subsequent notification to users that their system will reboot within 8 hours.

Yet, in the last 1.5 weeks, I've been forced to run Office Online Repair on 2 computers where the Ribbon, Menu and even the Quick Access Toolbar would not respond at all. Also, I could not even close the Outlook application except via End Task. It should be noted that the 2 computers both had additional Outlook profiles that use non-Exchange mail servers and PST files for storage.

Even so, I have no problem using OneDrive for common file synchronization and most of our clients take full advantage of it

Share via

Class outlook is not working properly after Windows 11 version 25H2 update

0 additional answers

Your answer