Missing Teams Contacts after Migration

When users were able to create contacts directly in Teams, those entries were stored only inside Teams and not in Exchange. Since Microsoft switched to the unified contacts model, all new contacts are saved in Exchange Online and sync automatically between Outlook and Teams. The problem is that the older “Teams-only” contacts don’t get carried over when you migrate mailboxes, so they seem to vanish once Teams starts using the unified model. Unfortunately, Microsoft doesn’t provide a built-in way to preserve them. The only workaround is to export or note down those old contacts before the migration and then re-create or import them into Exchange Online so they’ll sync properly going forward. It’s not ideal, but once everything is in the new system, contacts will be managed consistently between Outlook and Teams.

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