Your mail server certificate is invalid error

Anonymous
2018-03-03T15:59:06+00:00

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!!!!

Outlook | Outlook for mobile | Outlook for Android | For business

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  1. Anonymous
    2018-04-27T15:10:49+00:00

    I had a chat with Microsoft regarding this yesterday.  They have dropped support for TLS1.0 and 1.1 and are requiring TLS 1.2 if you want to use the app.  I am currently in process of bringing up a new 2008 R2 server to move my web facing traffic to, you can have multiple CAS servers so you do not have to remove/delete/decommission your existing, just add a new web facing server to take the role of internet facing owa/activesync/outlook anywhere (if you have it).

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  2. Anonymous
    2018-04-27T18:33:39+00:00

    This would be down to ISps to do this, not indivual users. Talktalk is not my ISP, but my email is Tiscali, which I have and have had when I was with Tiscali ISP, but they were taken over by tallktalk.

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  3. Anonymous
    2018-04-28T02:26:14+00:00

    I've got the same issue on mine as well. Updated to the latest app version 2.2.143 for android and the invalid certificate error has only just happened a couple of days ago. Tried uninstalling, re-installing, restarting even factory reset and nothing has worked. If Microsoft have updated the android and apple apps to only take TLS1.2 then its possible the the ISP's may not have updated yet or the app itself is still using the older 1.0/1.1 but this seems unlikely as I've also checked using the stock gmail app and it is working and accepting the imap.tiscali.co.uk address fine however they may also be using the older TLS1.0/1.1. I've also tried another app that kind of looks like outlook but isn't and its also working fine so what ever the problem is, It could be with the ISP's still using the older TLS certificates

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  4. Anonymous
    2018-04-28T08:28:21+00:00

    thanks

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  5. Anonymous
    2018-04-29T18:18:56+00:00

    A chat with support on the Outlook App for Android(yes if you click support they do respond) but they are TOTALL useless.  Claim that it is a certificate problem on our end.  Mail on Windows 10 and on my tablet work just fine and have only complain about the certificate one time when you first authenticate but when you say yes to do you want to connect anyway it works just fine.

    Microsoft needs to fix these problems ASAP or they will lose a whole lot of users.  Do you think its all in attempt to get people to move to the Outlook cloud?  That would be diabolical.

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