Clear Auto-Complete Cache
Go to the File tab and choose Options.
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In the Outlook Options dialog box, select the Mail tab.
In the Send messages section, clear the Use Auto-Complete List to suggest names when typing in the To, Cc, and Bcc lines.
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If you want to clear the auto-complete cache, select Empty Auto-Complete List. In the confirmation dialog box, select Yes.
Clear the cache to remove the auto-complete history without disabling the auto-complete feature in Outlook.
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In the Outlook Options dialog box, select OK.
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In the Outlook Options dialog box, select the Mail tab.
In the Send messages section, clear the Use Auto-Complete List to suggest names when typing in the To, Cc, and Bcc lines.
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If you want to clear the auto-complete cache, select Empty Auto-Complete List. In the confirmation dialog box, select Yes.
Clear the cache to remove the auto-complete history without disabling the auto-complete feature in Outlook.
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In the Outlook Options dialog box, select OK.
Updated on: 07/01/2023
Thank you!