Windows 10 reached EOS (end of support) on October 14, 2025. If you are on Windows 10, see this article.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Lolu chungechunge lwabekwa kunqolobane. Uyacelwa ubuze umbuzo omusha uma udinga usizo.

I have just installed Thunderbird, am continually getting "certificate for outlook.office365.com" not trusted

  • 1 baphendule
  • 0 zinale nkinga
  • 110 views
  • Igcine ukuphendulwa ngu Ed
  • Okugcinwe kunqolobane

I have just installed Thunderbird, am continually getting "certificate for outlook.office365.com" not trusted. I have added Thunderbird to my Malwarebytes exception list, but the the notice continue to come. I have ensured that OAuth2 is the correct authentication method, but the messages persist.

Is there something else I can do to stop these messages?

Would be very grateful, thank you.

Tim Harrison

I have just installed Thunderbird, am continually getting "certificate for outlook.office365.com" not trusted. I have added Thunderbird to my Malwarebytes exception list, but the the notice continue to come. I have ensured that OAuth2 is the correct authentication method, but the messages persist. Is there something else I can do to stop these messages? Would be very grateful, thank you. Tim Harrison
Ama-screenshot ananyekiwe

All Replies (1)

Sounds like your antivirus (not MWB) is intercepting the real cert. Which AV are you using?