The connection to the server has failed

The connection to the server has failed. Account: \\\'mail.xxx.xx\\\', Server: 'mail.xxx.xx\\\', Protocol: SMTP, Port: 25, Secure(SSL): No, Socket Error: 10060, Error Number: 0x800CCC0E

This usually means that port 25 is blocked on your PC or by your internet provider. Some providers are known to block port 25 (e.g. KPN direct ADSL).

In these cases, it is best to use your internet provider's outgoing mail server, often referred to as the SMTP server. Alternatively, you can change port 25 to port 465.