Mirrored database error

This error usually pops up when there's a leftover identity or cached credential from a previous Outlook profile or account setup attempt. Even if the account was removed, some traces might still be stored locally.

Here’s what I’d try:

1. Remove any existing Outlook profiles:

   • Go to Applications > Utilities > Outlook Profile Manager
   • Delete any profiles that might be linked to the same Outlook.com account

2. Clear cached credentials:

   • Open Keychain Access
   • Search for anything related to Outlook, Microsoft, or your email address
   • Delete those entries (make sure you know your credentials before doing this)

3. Reboot your Mac, then try adding the account again.

If that doesn’t work, try creating a new macOS user profile and add the account there. If it works in the new profile, then the issue is definitely local to your user environment.

Let me know how it goes.

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