SMTP error sending eMail from Thunderbird

This is not technically a SmarterMail problem, but I am not sure where best to post it.

From time to time, typically when I am travelling and staying at a hotel, I get the following message when trying to send eMail from Thunderbird

'The message could not be sent because connecting to SMTP server smtp.xxx.com failed. The server may not be available or is refusing connections'

This has happened multiple times.

In the case tonight, I successfully sent one eMail earlier, and then it failed on the second, so I don tot think it is an authentication issue.
I can, of course, receive eMail without problems.

Any help would be appreciated

TIA

marc

 

Hi,
Does it allow you to change the outgoing port to 587?