Clear old credentials
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Make sure that Outlook is closed.
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Click the Start Menu (or press the Windows key), and then search for Credential Manager.
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Windows 10:

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Windows 7 (or earlier):

 
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Click on Credential Manager to open it, and then click Windows Credentials.
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Under the Generic Credentials heading, find the credentials that have Outlook(15/16) and your email address.
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For example MicrosoftOutlook15:example@yourdomainexample.com It may not be exactly as shown, but use it as a base guideline.
 
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Click the arrow next to the entry to display it.

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On the detail page of the credential entry, click remove to remove the credential from the manager.

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Repeat this process for all credentials matching Outlook(15/16) and your email address. There may be anywhere from one to three entries listed.
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Close all windows, and re-open Outlook. When Outlook prompts for your credentials, enter the full email address and password for the mailbox, and check the box Remember My Credentials.
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If this process is successful, your Inbox should display, and mail should start syncing.