Microsoft Safe Links: General Information and Troubleshooting


Microsoft Safe Links is one component of the Exchange Online Protection (EOP) system that helps protect UT users from phishing, viruses, and other types of malicious email attacks. When a message is received, it will automatically be filtered by Safe Links if applicable. The server will modify any links found in the message so that they redirect through a Microsoft server before continuing to the original destination. The benefit of this is that the link can be scanned for security risks, and blocked if it appears to be malicious.

Requirements to Trigger Safe Links Filtering

Please note: Messages from both external and internal senders are filtered as long as they meet the criteria below.

  • The recipient must have an A5 Security Microsoft 365 license. This should include all active faculty/staff/students by default.
    • Generally, retiree, alumni, sponsored, and admitted student NetIDs are excluded.
    • Important! This means that ALL departmental NetIDs and shared mailboxes are excluded, because they do not receive an A5 license.
    • If you can log in to Microsoft 365, click here to check your license status. (Click "View subscriptions" if you are not automatically redirected to your subscription status)
  • The message must contain one or more hyperlinks with the http:// or https:// protocol. Other common protocols, such as mailto: and tel: will not be filtered.

Recognizing a Safe Link

It's easy to tell when a link has been filtered by Safe Links. When hovering over the link, check if the URL begins with the following:

Note: The number near the beginning that follows "nam" (for North America) may change periodically. This is normal. 11 was used as an example here because it seems to appear often.

Common Safe Link Problems

Safe Links typically do not cause a link to stop working, however, it can happen occasionally. See the list below for common indicators of problems with the system.

Symptoms of a Faulty Safe Link

  • Microsoft Safe Links, Exchange Online Protection, or Microsoft Defender error pages appear, instead of the expected page
  • Unexpected error codes when trying to follow an email link (400, 403, 500, etc.)
  • "Link has expired" or "Invalid URL" errors, even when the link should be valid

Problematic Links

Links with these features seem to cause problems with Safe Links more often than other types of links.

  • Links that are very long
  • Links containing unusual characters
  • Links with arguments included (e.g. "&source=abc" or "referrer=def" or "?query=ghi" and so on)

Can Safe Links be Disabled?

No. Safe Links is enabled at the UT system level, and cannot be disabled for individual accounts.


If you're having a problem with an email link, try these easy troubleshooting tips first:

  • Open the link in a Private Browsing window and see if it works there.
  • Try accessing the link from another browser or device.
  • Restart your computer.
  • Wait a while and try again. It could be a temporary problem.

If none of the above work, and you suspect that the issue might be with Safe Links, try following the steps below:

 Safety First

Doing this can sometimes fix links that aren't working, but you will no longer be protected by Safe Links.

Do not continue if the message seems suspicious, or you aren't sure where the link will lead.
If in doubt, stop. Contact the OIT HelpDesk for assistance at (865) 974-9900.

First, check the link in the email. Is it written out fully, such as "", or not, such as "Click here to go to the OIT homepage"?

If the link is not written out, only the HelpDesk will be able to recover the original URL. Please reach out for additional instructions.

However, if the link is written out, there is one option available. Try putting the text into your browser, rather than clicking the link. For a short link, like "", it would probably be faster to just type it. With longer links, this would be more difficult. In this case, try copying and pasting the text, rather than the link address, into your browser. Be careful not to accidentally catch any extra punctuation as you make the selection.

If the link still isn't working, contact the HelpDesk for further assistance.


Article ID: 139536
Wed 5/11/22 9:53 AM
Fri 10/20/23 2:19 PM
EOP/Spam Quarantine
Microsoft 365