Outlook 365 not opening in Windows 11

Thank you @David Blaney - your solution (Win+R then outlook.exe /resetnavpane) solved it for me!
My incident was caused due to my machine not being able to un-hibernate, ever since upgrading to Windows 11.

This time I had Outlook and several other apps open when I hibernated the machine, the subsequent restart failed, and I had to reboot the machine.

Only to then discover that Outlook was hanging on launch. (sigh).

Yes - this works. Although I chose 'quick repair' - not 'online repair' - and that worked too!

Restart Outlook a couple of time to correct the problem that Outlook won't start? Am I understanding you correctly?

Hello, it seems that I cannot open Outlook in safe mode. As soon as I click ok on the run button, I get a Windows security box that opens asking for my Outlook credentials. I am trying to connect with an Exchange server at work. I have successfully connected for years and then just started having problems. I am running Windows 11 on a one year old PC.

*I type in the credentials (just the password, the username is already there)

*The box disappears and then immediately comes back asking for log in credentials again

*I have entered log in credentials several times, finally hit "Cancel"

*A box pops up with the following:

Cannot start Microsoft Outlook. Cannot open the Outlook window. The set of folders cannot be opened. You must connect to Microsoft Exchange with the current profile before you can synchronize your folders with your Outlook data file (.ost).

*I have uninstalled and reinstalled Microsoft Office365 three times. The installation says that it is fine and all of the MS apps open without issue except Outlook. When the MS apps first open the same box asking for the password comes up but goes away without incident and the app opens.

Thanks. Joe

Thanks Mark,

The quick repair option worked for me in this instance and I would suggest try this first before going down the longer online route. Top tip though chap. Thanks.