I have a VM on Google Cloud running Ubuntu 18.04.5. Having an issue setting up iOS (mobile) and Thunderbird (desktop) mail client for a domain, which tells me it’s not the client itself nor the device that’s the problem.
I’ve tried with and without VPN.
I’ve tried to disable Failed2Ban temporarily.
I’ve tried the hostnames mail.domain.com and simply domain.com without resolution. I’ve tried resetting the mail account password.
Initially it tells me that it cannot connect with SSL and to try without, even though I have a wildcard SSL from Let’s Encrypt. Then it’s still not able to connect.
Webmail works fine.
Perhaps someone in the community can point me in the right direction?
I’ve tried with and without VPN.
I’ve tried to disable Failed2Ban temporarily.
I’ve tried the hostnames mail.domain.com and simply domain.com without resolution. I’ve tried resetting the mail account password.
Initially it tells me that it cannot connect with SSL and to try without, even though I have a wildcard SSL from Let’s Encrypt. Then it’s still not able to connect.
Webmail works fine.
Perhaps someone in the community can point me in the right direction?