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I am attempting to use Outlook on my android phone. When I attempt to add my email account to outlook (on my phone) I get an error that says: Your mail certificate is invalid. Would you like to login anyway. PLEASE HELP!!!!
Using Outlook for Android in business environments for email and scheduling
Locked Question. This question was migrated from the Microsoft Support Community. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.
Thanks for the mention of using BlueMail. I've just installed it and it's actually better than MS Outlook which I have now uninstalled on my S7 edge and waved bye bye to!
Nice one !
+1 here. We're also seeing this issue on Android devices within the past 24 hours.
We have hundreds of users complaining that they cannot receive e-mail. If MS haven't issued a fix within the next few hours then we'll have no option but to start migrating users to the gmail app instead. We just cannot have users disconnected for what is already a prolonged period of time. Once our users are onto gmail, we won't be moving people back due to the amount of work it causes our department and the disruption it causes our end users.
Experiencing the same issue. As of April 25th, at least 20 users have complained of email connection issues.
On Android - Login Error - Your mail server certificate is invalid. Would you like to log in anyway?
On iPhone - Connection Warning - Your mail server certificate is invalid. Would you like to login anyway?
If the users taps Login, it will just keep prompting them with the same pop-up to login or cancel.
The certificate is valid and was renewed/replaced March 20th 2018. We are using Exchange 2007 and ISA server. This is impacting anyone with a mobile phone (iPhone and Android) using the Microsoft Outlook mobile app. If the users switches to the native gmail or apple mail client they do not get a certificate error. This is not impacting our Microsoft Outlook clients on PC.
I guess its time to send an email out to 2000 users and ask them to switch from Microsoft Outlook to the native iPhone email client.
Same issue here with timewarner/spectrum. This is really frustrating as it will once and a while work, and after a few days does this again. Problem seemed to arrive with the beta rollout......
I am seeing the exact same thing.
This issue coincided with getting a new certificate installed on our Exchange server, but OWA works fine and all other users have no problem with their phones or ActiveSync relationships. Only issue is with this single iPhone 6Plus using the Outlook for iOS app.