Issue: Outlook keeps asking for credentials
Solutions from Microsoft: https://community.office365.com/en-us/f/172/t/15620
This issue can be caused if one of the following factors is true:
1. The Always prompt for logon credentials box is checked.
2. Office 365 Desktop Setup has not been run, or the Microsoft Online Services Sign In Assistant is out of date.
3. The personal certificate needs to be refreshed.
Based on this situation, please perform the following steps to troubleshoot this issue.
Check Outlook settings
1. Open Outlook 2010. Click File>Account Settings>Account Settings.
2. Click the E-mail tab, click the Exchange Online mailbox, click Change…
3. Click More Settings…. Click the Security tab, make sure the Always prompt for logon credentials box is unchecked.
Run Office 365 Desktop Setup Apps
To do so, please log on Office 365, click Downloads under Resources on the right panel, and then click Set up under Set up and configure your Office desktop apps.
Delete the personal credentials
If you are running Windows 7, please also remove the user’s stored credentials in Windows Credential Manager.
To do this, follow these steps:
a. Click Start, click Control Panel, and then click Credential Manager.
b. Locate the set of credentials that is used to connect to Exchange. The credentials should be shown as MS.Outlook: email@example.com or username@your vanity domain.com
c. Expand the set of credentials, and then select Remove from Vault.
If you are using Microsoft Office 2010: (from Microsoft https://community.office365.com/en-us/f/172/t/268139)
1. Clear the user credential from Credential Manager:
- Click Start, click Control Panel, and then click Credential Manager. Note If View by is set to Category, click User Accounts first, and then click Credential Manager.
- Locate the set of credentials that has Outlook in the name.
- Click the name to expand the set of credentials, and then click Remove from Vault.
- Repeat step 3 for any additional sets of credentials that have the word Outlook in the name.
2. If the Office 2013 is not downloaded from the O365 portal, try uninstalling it
and re-installing from the portal if possible. If using Office 2013, and Outlook keeps
asking for your username and password try creating another profile for Outlook. You
can call it anything you want to and tell Outlook to use the new on as default.
A profile consists of accounts, data files, and settings that specify where your email messages are saved.
- Exit Outlook.
- In Control Panel, click or double-click Mail.
- Click Show Profiles.
- Click Add.
- Type a name for the profile, and then click OK.