error connection IMAP


Verified User

I try to connect from a webapplication on a subdomain to IMAP for email piping.

I set imap server (, username and password with TLS and also with SSL, but keep getting (cronjob) this error:

Could not authenticate to IMAP server. Please check your IMAP server configuration in System > System Settings > Tickets.<br>Processing Escalation Rules<br>Auto Closing TicketsPHP Notice: Unknown: TLS/SSL failure for SSL negotiation failed (errflg=2) in Unknown on line 0

when I run telnet -server-ip 143 imap is OK

I have no idea what causes this. With Thunderbird I connect to IMAP without any problems (SSL/TLS).


Super Moderator
Hello Fred,

So you have a valid cert for in Dovecot?

Will you provide a real domain name so that I could check it for you?


Verified User
First thank you for your answers.

Yes I have a valid certificate and with Thunderbird I can access Imap on port 993 without any problem. So first thought it was a bug in the application, but when I use it with Gmail Imap, it connects without problem. Maybe it has something to do with authentification method. In Thunderbird I can set it to normal or encrypted...but it is just guessing.
Last edited:

Richard G

Verified User
When I do a test on with port 993 all is oke.
However, when I do a check with port 143 it says:
No SSL certificates were found on Make sure that the name resolves to the correct server and that the SSL port (default is 443) is open on your server's firewall
Which seems normal to me as this is no SSL port.
Does your cronjob uses port 993? Because that's not clear to me at this moment. And you can't use ssl on port 143.

I also see that an ipv6 is found for that hostname, but says:
Unable to connect to the server
Probably does not have anything to do with it, but maybe something you want to look in to for other reasons.

I'm curious about what zEitEr will find.


Verified User
I think it must be something wrong in the script. I was affraid overlooking something. Probably the "wrong" port is called. Ipv6 is right, there is a problem with a router at the datacenter. I need to dig into the script. Thanks again.