Outlook became unusable. I tried switching to the webmail, but my workflow is such that I essentially stopped checking email for last week. Meeting invites went unseen. Notifications missed my attention. Every strategy I tried to ensure that I saw the email and calendar were ineffective. So, I kind of need the application to work.
The issue appeared to be some kind of file corruption. The application would crash due to “a problem.” When I opened the application, it would claim there was an issue with the data file and ask to repair it. I allowed it. It would make a backup and repair the file and tell me all is good. Things would be fine for a while until it happened again.
Back in November it just happened twice. Then in early December, it was a couple times a week. In mid-December, it was a couple times a day. Finally, today, it would only stay open for a couple minutes.
I decided that since my data is on Exchange, that deleting the files should not really be catastrophic. Outlook should just rebuild the data files for me. So, I renamed the data files. (“Should” != “definitely would.”) They are located in C:\Users\<username>\AppData\Local\Microsoft\Outlook and have the file extensions .ost or .pst. I chose to rename them with “bad_”. I started Outlook again. It rebuilt the data files. I have not seen a crash since.
My guess is the repair did not actually fix the problem. Certainly, the repair tool kept identifying things to fix.