Outlook 365 not opening in Windows 11

Ok folks, I spend a day battling this issue: Context:

1. New HP gaming PC running windows 11
2. Loaded my needed software and configured Microsoft 365 Outlook to Road Runner webmail via IMAP
3. After 4 hours of getting my new machine set up and customized, I was pretty impressed and had fun learning windows.
4. Shut down the machine for the night.

Problem:

The next day, outlook had a pop-up modal indicating that the .ost file was corrupted. It tried to recover but then outlook would not open without the error modal popping up. I researched all day to find the solution after 4 uninstalls and reinstalls of Microsoft 365. The app would not even start in safe mode. Skipping all the things I tried accept the final success, here is what you should try:

1. Uninstall Microsoft 365
2. restart
3. open the registry editor tool and drill into the :
4. HKEY_CURRENT_USER folder tree
5. locate Microsoft sub folder
6. locate the Office sub folder
7. Right click on the Office folder and select delete from the action pop up.
8. restart
9. Install Microsoft 365
10. open Outlook
11. set up your IMAP configuration for your mail provider
12. It worked!

Not sure what caused the original corruption and launch issues with outlook. I had Norton scan the PC and got the all clear.

Hope this helps you as it may save your hours of remediation effort.

WOW worked for me too.

This worked for me!!!! Thank you so much!!!

you're welcome

Of all the replies for fixes, this one worked for me. Thank you!