Tip 801: Block hyperlinks in Outlook

I recently had a question from an administrator looking for a way to prevent users from clicking on hyperlinks in Outlook. He doesn’t care if users copy the URL and paste it into a browser, he just doesn’t want them clicking links in Outlook.

Links in the junk mail folder are unclickable, but you can’t block urls in other folders in the same manner. However, you can take advantage of a fairly common problem to make the links unusable. 

While most users want to fix the "This operation has been cancelled due to restrictions in effect on this computer." error, you can force this error in Outlook (and other programs) by editing a registry key.

Browse to this key


Then rename or delete the command key and when a link is clicked in Outlook, the user will receive an error message. (You'll need to restart Outlook after setting this key, as it reads it from the registry when it starts.)

Error message that links are blocked

I renamed my key


Video Tutorial

More Information

If you need to fix the 'Restrictions in effect' error and solutions, see This operation has been cancelled due to restrictions in effect at Slipstick.com

Published November 10, 2010. Last reviewed on May 8, 2014.

  • Kaushick Krishna Moorthy


    Thanks for you post. But i have tested it in my pc, its not working. I have deleted the above key as mentioned. But still i didn't get any error message. The links are opening without any issues.

    Please advice



  • Diane Poremsky

    Rather than deleting it, rename it - HKEY_LOCAL_MACHINE\SOFTWARE\Classes\htmlfile\shell\_open\_command - but you also need to restart Outlook for the key to work in Outlook.