Unable to connect IMAP account with encryption

Operating System & Version
cPanel & WHM Version


Apr 11, 2020
cPanel Access Level
Root Administrator
Cannot set up email account on both outlook and Thunderbird when using IMAP on port 993 with any encryption method nor POP3 on port 995 with SSL/TLS (although these are the settings given in Cpanel, however I can connect successfully on both IMAP and POP3 with same log in credentials but no encryption(ports 143/110/587).

ERROR ON OUTLOOK 2016 WIN10 "Something went wrong. We couldn't to the incoming (IMAP) server using the specified encryption method. Please check the incoming (IMAP) server encryption method and try again."

Any help will be highly appreciated.


Product Owner II
Staff member
Nov 14, 2017

Its more difficult for me to test on Outlook (though I can if necessary) but I can easily on thunderbird and mac mail. Does the issue persist when you use the Auto Config tool for thunderbird or Outlook? You can find this in cPanel>>Email>>Email Accounts ->> Connnect Devices (next to the email account you want to set up) -> Mail Client Automatic Configuration Scripts. It's also sent via email when the account is created.

If you have AutoDiscovery enabled in WHM it should also be able to autodiscover the settings. I set up a test account in Thunderbird to ensure that the settings in cPanel's manual config were correct as well and I'm receiving no errors:

Server Settings (Thunderbird)
Servername: mail.mydomain.tld
Username: [email protected]
Port: 993
Security Settings: SSL/TLS
Authentication Method: Normal Password

Outgoing Server (SMTP)
Description: my email account name
Servername: mail.mydomain.tld
Port: 465
Connection Security: SSL/TLS
Authentication: Normal Password
User Name: [email protected]

If this does not work properly for you on your server you should be checking a few things:
1.is the port open in the firewall? One way to test this is to run something like the following from outside the server:
nmap -Pn yourdomain.tld -p993
2. Is there an SSL installed on the domain?

3. Does the hostname have an SSL if the domain does not?

4. Does the Server Name listed in the mail configuration settings as provided by cPanel resolve (it should when the information is created but DNS issues can happen)