Microsoft Defender blocking TeamRetro links for some Microsoft 365 customers

Update timeline

1. investigating Oct 15, 2026, 02:30 AM UTC

   Some customers who use Microsoft 365 see a "This website is classified as malicious" warning from Microsoft Defender when they open TeamRetro links, including meeting and health check invites. TeamRetro is safe to use, and other ways of reaching TeamRetro are not affected. The warning followed abuse of TeamRetro free trials by a third party, which we have now stopped. We have asked Microsoft to review and remove the warning. Until Microsoft clears it, your Microsoft 365 administrator can allow TeamRetro for your organization. In the Microsoft Defender portal (security.microsoft.com), go to Actions & submissions > Submissions > URLs, submit https://secure.teamretro.com as "Should not have been blocked", and select "Allow this URL". We'll post an update here when the block is cleared. If you need help, contact [email protected].

2. investigating Oct 15, 2026, 02:30 AM UTC

   Some customers who use Microsoft 365 see a "This website is classified as malicious" warning from Microsoft Defender when they open TeamRetro links, including meeting and health check invites. TeamRetro is safe to use, and other ways of reaching TeamRetro are not affected. The warning followed abuse of TeamRetro free trials by a third party, which we have now stopped. We have asked Microsoft to review and remove the warning. Until Microsoft clears it, your Microsoft 365 administrator can allow TeamRetro for your organization. In the Microsoft Defender portal (security.microsoft.com), go to Actions & submissions > Submissions > URLs, submit https://secure.teamretro.com as "Should not have been blocked", and select "Allow this URL". We'll post an update here when the block is cleared. If you need help, contact [email protected].