Today, I have spent 7 hours trying to fix issues caused by a MS Office update. The customer has Office 365 and 4 computers all stopped receiving emails this morning.
After deleting profiles and deleting passwords in CREDENTIAL MANAGER, I managed to find a REG entry that was causing the issues.
- First of all login to your mail account online (if you can) and make sure all your emails are intact. for my customers this is done by going to login.livemail.co.uk
- Remove the account in Outlook. Once you’ve confirmed that everything is complete, you can go to Outlook and remove your Exchange account from there. You can add it later. Just make sure you have the right password. Open the Outlook app.
Click File > Account Settings> Manage Profiles> Email Accounts.
Under Email Accounts, click your Outlook.com account and select Remove at the top.
NOTE: If this is the only account in your Outlook profile and you’ve set it as the default, you may not be able to remove the account. In this case, you’ll need to create a new Outlook profile, set it as deaf, and re-add the account later. - Erase all Outlook credentials saved in Windows Credential Manager. This will allow you to clear the old passwords for this account outlook.com saved in Credential Manager and have the opportunity to add the latest credentials to the account through reauthentication. When you do this, make sure that Outlook is closed. Here’s how to do it.
Press Windows Key + R to open the Run dialog box.
Type control keymgr.dll and press Enter.
In the Credential Manager window, double-click the Windows Credentials tab
Scroll down to find your Outlook-related credentials.
Press the credential you want to remove, then press the Delete button twice
Double-click Yes in the pop-up window to confirm the action. - Delete the Outlook “Identity” folder in the registry. Please note that this troubleshooting is early and can cause serious problems if not done correctly. Be sure to back up your registry first. To back up the registry, open Registry Editor or type regedit from the search menu, and then run as administrator. Make sure “Computer” is highlighted, hit “File” > “Export> then select the location you want to save, then hit “Save“.
After that, go to: HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Common\ Identity and delete the Identity folder. - Add your account back in Outlook. Now try to open Outlook and add your account again. Make sure you enter your password correctly to avoid authentication errors. For information, see this article Add an email account to Outlook
- Try resetting your password. If the problem is the same, you may need to reset your password and see if that helps.