Outlook/hotmail accounts won't connect every other day/week

Help
1

is it Outlook or Mailspring and why can’t it be fixed?

2

This is primarily a Microsoft issue, not a Mailspring one — Microsoft has been aggressively enforcing token expiration and periodically deprecating older authentication methods for personal Outlook/Hotmail accounts.

A few things that help:

  1. Reconnect via OAuth — In Mailspring, go to Preferences > Accounts, select your Outlook account, and click “Reconnect.” Choose the Microsoft login option (not manual IMAP) so it uses OAuth tokens instead of a password, which tend to be more stable.

  2. Check for “less secure app” policies — Microsoft sometimes silently revokes access for IMAP clients. Signing back in through the Reconnect flow usually restores it.

  3. If using IMAP/SMTP manually — Microsoft requires “Modern Authentication” (OAuth) for personal accounts now. Adding the account through Mailspring’s built-in Microsoft option (which uses OAuth) is more reliable than manual IMAP setup.

Unfortunately the frequency of these disconnects is determined by Microsoft’s token lifetime policies, which we can’t control on our end.