can no longer connect to my mail server

Question

Worked until today. Using same credentials and protocol

tried to "repair" outlook, but it runs forever with no end

Answer 1

Hi Jay Cohen

Thank you for reaching out to Microsoft Q&A Forum! I understand how frustrating it is when Outlook suddenly stops connecting to your mail server, especially since it was working fine earlier.

Just to confirm, what type of account is this, Outlook.com/Hotmail or a third‑party provider (Gmail/Yahoo/custom domain)? And do you see any specific error message on the screen when it fails to connect?

In the meantime, please try the following steps:

1. Fully restart Outlook

• Close Outlook completely
• Press Ctrl + Shift + Esc to open Task Manager, find "Outlook" in the list, right-click it, and select End Task to ensure no background processes are still running. Or restart Windows first, then open Outlook.

2. Check Work Offline mode

• In Outlook, go to Send/Receive tab at the top > make sure Work Offline is not enabled.

3. Test Outlook in Safe Mode (rules out add-ins)

• Close Outlook completely
• Press Windows + R > type: outlook.exe /safe > press Enter
• If it's stable in Safe Mode, an add-in is the likely trigger. In that case, disable add-ins in normal mode and re-enable them one by one.
  • Go to File > Options > Add‑ins > Manage: COM Add‑ins > Go…
  • Uncheck all unnecessary add‑ins, restart Outlook and re-enable one by one to find the culprit.

4. Test with Outlook Web

• Go to Outlook on the web
• Try signing in there to see if the issue persists

5. Check your internet connection or try a different network/ device

Make sure your device has a stable internet connection and try switching networks (e.g., from Wi-Fi to mobile hotspot) then test again.

Please let me know how it goes after trying these steps. Thank you for your understanding.

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Answer 2

If you're unable to connect to your mail server in Outlook and have already tried repairing it without success, there are a few steps you can take to troubleshoot the issue:

1. Check for Service Issues: If multiple users in your organization are experiencing similar issues, it could be a service problem. Check the Microsoft 365 Service health status to see if there are any ongoing issues with Exchange Online.
2. Run Windows Update: Ensure that your Outlook client and Windows operating system are up to date. Outdated software can lead to connectivity problems.
3. Use the Microsoft Support and Recovery Assistant: This tool can help diagnose and fix common Outlook connectivity issues. You can download it and follow the prompts to troubleshoot your connection problems.
4. Check TLS Settings: Ensure that your environment is using TLS 1.2 or later, as older versions (TLS 1.0 and 1.1) are deprecated and may cause connection issues. If your Exchange Server or Windows Server is using an older version, you may need to update it.
5. Verify Credentials: Double-check that you are using the correct credentials and that there are no changes to your account settings that could affect connectivity.

If these steps do not resolve the issue, consider reaching out to Microsoft support for further assistance.