Tiscali emails are still not being delivered

Any TalkTalk customers here will understand this problem. I'm with them but still retain my Tiscali email address and this applies to all the Tiscali customers when TT took Tiscali over. Since then there have been a multitude of email problems on a regular basis.....so many I've lost count. The current problem is a tricky one. Along with many others I can receive but not send emails using Windows Live Mail. This has been going on for at least a week to my knowledge, maybe longer and the forums are littered with posts all describing the same symptoms...can receive but not send. I've phoned their so-called help line and been instructed to change my WLM settings, port details etc, all to no avail. I have a separate Gmail account and this works perfectly through WLM. Any help would be greatly appreciated.

Tiscali emails are still not being delivered