Configuring preferences and options in Outlook.com
PS - have you tried to reset any of your Outlook passwords (normally) to see what, if anything, happens?
me, I haven't gotten around to that yet, but it "might" work
note - generally it is difficult to reproduce this error on demand, but I have discovered that when creating a new test profile for just 1 account, pop-up always appears as soon as Outlook is launched, so that's good to know if you change a password as a test
- jonathan