Setting the IP address of the DNS server manually did not help (neither to the local DNS nor the Google's DNS). What worked, was entering the IP address of the SMTP server manually (which, of course, defeats the purpose of having domain names in the first place). Of course, the SMTP port has to be enabled in the firewall.
System Log Information The specified SMTP server IP address could not be found in the DNS server. SMTPC: failed to connect smtp server. timeout. Connection to the SMTP server failed due to timeout. This could be because the specified SMTP server name is incorrect, or no connection to the network has been established, or the network configuration is incorrect, so connection to outgoing server smtp.gmail.… - Apple Community Aug 05, 2017 [SOLVED] Ricoh Scan to email - MP C400SR - Printers Dec 05, 2014 Troubleshooting | OKI Data
SMTP ERROR: Failed to connect to server - Microsoft® Community
Fix iPhone Error "Cannot Get Mail: The connection to the Check the Internet connection on iPhone. First thing to check is your Internet connection. Whether … 'SMTP connect() failed' error on localhost · Issue #368 My settings are true and I can send mail from server but I updated my localhost PHP version to 5.6.3 and now I can't send mail. I get an error like this Warning
How to Fix SMTP ERROR: Failed to connect to server
Thunderbird Failed to Connect to Exchange Server: Automated Solution. Another best solution to this is to perform this without Thunderbird so the time that user spends on Thunderbird will be eliminated. To perform like this user have to Convert Thunderbird MBOX to PST.