I solved the problem! It is stock android 5 (Moto G, GPE) with stock mail, by the way. It happens on multiple devices.
It is like this: The mail client connects to my mail server. The mail server is called "mail.domain.tld". Now, another domain name on the same server (other.domain.tld) is supplied to the mail client by apache, while the certificate itself is served by the mail server (dovecot, postfix, ..). Obviously, the name of the domain now does not match the certificate. What I had to do was to add mail.domain.tld to the apache vhosts and make it the first to be served by appending 000_ at the beginning of the name of the vserver config. Now, name and certificate do match. I wonder why apache serves the mail client in the first place... Adrian > Am 22.02.2016 um 21:07 schrieb André Schild <an...@schild.ws>: > > Am 22.02.2016 um 17:42 schrieb Adrian Figueroa: >> Actually, I did provide the analyzer with valid login information. Maybe I >> should not pay too much attention to that 401 error. >> ActiveSync does work on any other device, also on Android with other clients >> (such as "nine"). >> >> Could it be, that Let's Encrypt certificates do not work on Android with the >> standard mail client? They do work in browsers. > > Are you using Stock Android, or some other branded Android device? > Some manufacturers make modifications to such services... > > Does it happen on different devices? > > What Android Version? > > André > -- > users@sogo.nu > https://inverse.ca/sogo/lists
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