Couldn't reach server. Please double-check the server and port number.

GoWilkes

Well-Known Member
Sep 26, 2006
613
25
168
cPanel Access Level
Root Administrator
I found earlier threads on this, but no real solution.

I have all of my incoming emails forwarded to Gmail, then use my account's SMTP to send email. This works perfectly in Thunderbird and on my phone, but trying to set it up in Gmail (under Settings > Accounts and Import > Send mail as) gives me the error:

Couldn't reach server. Please double-check the server and port number.

I'm using the exact same setting as Thunderbird and my phone, which I double-checked by logging in to Webmail then clicking on "Configure mail client". I tried using SSL and non-SSL, and either had the same error or an error saying that the server couldn't be reached.

Any suggestions?
 

cPanelMichael

Administrator
Staff member
Apr 11, 2011
47,908
2,216
463
Hello :)

Could you verify if your server's firewall is blocking access to Google's IP addresses? You may want to install a firewall management utility such as CSF if you have not already done so.

Thank you.
 

GoWilkes

Well-Known Member
Sep 26, 2006
613
25
168
cPanel Access Level
Root Administrator
I think I got it to work! I had to add all of these to the firewall whitelist (which is CSF):

Code:
209.85.137.9
209.85.139.9
209.85.128.0/17

64.233.161.9
64.233.160.0/19

72.14.235.9
72.14.192.0/18

74.125.0.0/16
I still couldn't connect using port 25, but was able to connect using port 465 over SSL.

Hopefully this list of IP's will help future users. Thanks, all!
 

cPanelMichael

Administrator
Staff member
Apr 11, 2011
47,908
2,216
463
I am happy to see you were able to address the issue. Thank you for updating us with the outcome.