Resolved Gmail 'Couldn't reach server. Please double check the server and port number' error

[deepakdhingra]

Hi,
I was able to connect my accounts on my Plesk Cloud Server to my Gmail accounts for the last several months without any issues. It has stopped connecting after 26th of July, 2021.
POP3 still connects and mails can be retrieved in my Gmail account but SMTP on 587, 465 and 25 just doesn't connect.

I have read a few posts with this particular error but none of the solutions worked for me, for some reason. I am using Version 18.0.37 Update #1.

Is there any new solution for this?

Any help would be appreciated.

 

[abusous2000]

I confirm the same error however it while authenticating my smtp server that is hosted by network solutions

This just started to happen in the last week

Were you able to resolve it?

 

[Bitpalast]

There are some reports that removal and restore of the mail collector in the GMail account solves the issue.

If not, maybe the GMail IP has been blocked due to wrong login attempts on your Plesk server. You may have set-up the connection correctly but some time along you may have changed the password of your mailbox, hence from that moment Google was unable to connect to your server and Fail2Ban has started blocking their IP for invalid login attempts. To check this, you can temporarily disable the Fail2Ban Dovecot (or Courier) jail.

Finally, GMail tries to use IPv6 first and, if unavailable, falls back to IPv4. If you have an IPv6 record configured in your DNS for the server's hostname (the mail server name), make sure that the mail server can actually be reached on that IPv6 address.

 

[deepakdhingra]

Yes, I was able to resolve it. I had done what Peter mentioned in the first part of his reply. I disabled Fail2Ban and it worked. But I hadn't changed my password anytime before that. So I do not know why Fail2Ban blocked the Google IP in the first place.

Hope this helps.

Deepak