This support article provides instruction how to purge the contact auto-complete within Outlook. This addresses issues that can occur when contacts within the auto-complete feature are corrupted. This is a known issue by Microsoft.


WARNING: This procedure clears all contacts within the Outlook Auto-Complete feature.
This does not remove any saved contacts within your Outlook account, but the cached
email addresses themselves. Exercise caution when performing this action.


Solution:

  1. In Outlook, go to File > Options


  2. Select the Mail category options, then click the Empty Auto-Complete List button

  3. Restart the Outlook desktop app


This will purge and remove all cached contacts within the Outlook Auto-Complete feature.



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