Outlook 2013 Continually Prompting For Credentials

Question

After migrating to Office 365 & installing Pro Plus 2013, Outlook 2013 (32-bit) continues to prompt for credentials even though it shows the mailbox as connected to Exchange.
To stop this prompt, I've done the following:
Removed Outlook credentials from credential manager
Removed/recreated Outlook profiles & renamed "outlook" folder found at C:\User\"username"\AppData\Local\Microsoft\ to "Outlook.old" so Outlook will recreate the folder upon restart.
Checked Security tab of "more settings" of the mailbox to make sure "Always prompt for logon credentials" isn't checked.
Please someone give me guidance as to what else the issue could be.

Answer 1

Hello,
How did you set the Logon network security under More Settings on the Microsoft Exchange
Security tab? Please make sure it's not set to a value other than
Anonymous Authentication.
To verify this, please follow these steps:
1. Launch Control Panel.
2. In Control Panel, locate and click
Mail.
3. Click Show Profiles, select your Outlook profile, and click
Properties.
4. Click E-mail Accounts, select
Account Settings and on the E-mail tab, click Change.
5. In the Change Account dialog, click
More Settings.
6. In the Microsoft Exchange dialog, select the
Security tab.
7. From the Login network security
dropdown, select Anonymous Authentication and click
OK.
8. Click Next and click
Finish, and then click Close on the Account Settings dialog.
9. Click Close on the
Mail Setup dialog, and click OK to close the Mail control panel.
Please let me know the result.
Reagrds,
Steve Fan
Forum Support
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