e-mail account stopps syncing

Question

Hi I have an E-mail account which stopps Syncing.

After a clean up of My PC one of my 2 Exchange E-mail accounts stopps syncing.

I have removed the account and tried to re-install, but I am in a constant loop of asking Password and refreshing security token.

What can I do?

Answer 1

Hi @matthiasmagitec,

Welcome to Microsoft Q&A, and thank you very much for reaching out.

Based on your description, may I verify whether you’re experiencing a sign‑in issue with one of your Exchange accounts, such as being repeatedly prompted for a password or seeing a security token refresh loop?

If you are encountering a password prompt loop, this might happen if Outlook is holding a corrupted or expired authentication token in Windows Credential Manager. In this state, Outlook continues validating against the broken token, even though the password itself is correct, which results in repeated sign‑in prompts.

In this case, aside from Q&A assist troubleshooting steps, you can try these following steps below to see if it able to solve your issue:

Clear cached Outlook / Office credentials:

Please close Outlook first, then open Credential Manager from the Windows Start menu. Under Windows Credentials, remove any entries related to Outlook, MicrosoftOffice, or Office16. After removing those entries, restart Outlook and sign in again. This forces Outlook to request a fresh authentication token instead of reusing the corrupted one.

I also found an external article mentioned this issue, feel free to check it here to see if it able to help you further.

Note: This information is provided as a convenience to you. These sites are not controlled by Microsoft, and Microsoft cannot make any representations regarding the quality, safety, or suitability of any software or information found there. Please ensure that you fully understand the risks before using any suggestions from the above link.

New Outlook profile:

If the issue continues, please try creating a new Outlook profile, as creating a fresh profile forces Outlook to rebuild the connection. You can try this by close Outlook, press Windows + R and type outlook.exe /profiles. On dialog box, click Options > New to create new Outlook profile. Tick on "Set as default profile" to ensure new profile is running when booting up Outlook.

Check for Cached Credentials in the Registry:

Press Win +R and type regedit to Open the Registry Editor. Then navigate to HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Common\Identity\Identities. Check and delete any entries related to the accounts you want to remove.

(Note: Serious problems can occur if you modify the registry incorrectly. Before making changes, back up the registry to restore it in case something goes wrong. For more details: How to back up and restore the registry in Windows

Besides these steps, may I know that did your IT admin recently change MFA or authentication policies? This often occurs when CA requires device compliance, has a short sign‑in frequency, or forces fresh authentication for Exchange Online specifically.

For reference:

Reauthentication prompts and session lifetime for Microsoft Entra multifactor authentication

https://techcommunity.microsoft.com/blog/microsoft-entra-blog/prompt-users-for-reauthentication-on-sensitive-apps-and-high-risk-actions-with-c/4062703

I highly advise that you should contact your IT Admin and check with them if applicable.

I hope this helps.

---

Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.

Answer 2

If your Exchange email account is stuck in a loop asking for a password and refreshing the security token, you can try the following steps:

1. Check Internet Connection: Ensure that your internet connection is stable and working properly.
2. Clear Cached Credentials: Go to the Windows Credential Manager and remove any stored credentials related to your Exchange account. This can help reset the authentication process.
3. Use Safe Mode: Start Outlook in Safe Mode by holding the Ctrl key while launching Outlook. This can help bypass any add-ins that might be causing issues.
4. Repair Outlook: Use the built-in repair tool in Outlook. Go to Control Panel > Programs > Programs and Features, select Microsoft Office, and then click on "Change" to find the repair option.
5. Create a New Profile: Sometimes, creating a new Outlook profile can resolve syncing issues. Go to Control Panel > Mail > Show Profiles and create a new profile, then add your Exchange account to it.
6. Check for Updates: Ensure that your Outlook and Windows are up to date, as updates can fix bugs and improve performance.
7. Review Security Settings: Check if there are any security settings or policies in your organization that might be affecting the account.
8. Contact IT Support: If the issue persists, it may be beneficial to contact your IT support team for further assistance, especially if this is a work account.

These steps should help you troubleshoot the syncing issue with your Exchange email account.

---

References:

• EAS devices still sync after an account is disabled or a password is changed
• Cant get into outlook - Microsoft Q&A