How do you fix This request is blocked. Ref A: Ref B: Ref C: Error?

Question

I have a user that is getting this error when they try to open an excel file in Teams. They can open the file in the desktop app but when trying to open within Teams they are getting this error.

Answer 1

Hi @Ray Allen (US)

Do you default to opening in the browser when you open files in Teams?

According to research, the issue may be due to an updated list of potentially malicious IP addresses obtained by the Web Application Firewall (WAF) to protect Microsoft 365 for the web.

Microsoft will fix this issue in the near future.

We recommend that you use the desktop client to open the file in the near future. If you are in Teams, please click the three-dot logo on the left side of the file and click the Open option and then select Open in app.

---

If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".

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

It's happening users select Edit in Teams.