Windows Live Mail – Emails stuck in Outbox

Hi,

I have not changed any settings in Windows Mail nor installed any new software and it has been working fine for the last 2-3 years. However, since yesterday I suddenly can't seem to send emails using my default Talk Talk (previously Tiscali) email address as the emails seem to remain stuck in the Outbox. There is no similar problem when sending emails from my secondary Gmail account using Windows Live Mail.

I get the following error message:

An unknown error has occurred.

Subject 'Test Email'

Server Error: 554

Server Response: 554 cm11gb1 smtp.talktalk.net ESMTP server not available

Server: 'smtp.tiscali.co.uk'

Windows Live Mail Error ID: 0x800CCC6F

Protocol: SMTP Port: 25

Secure(SSL): No

I have looked at a couple of other threads and can't seem to find a definitive answer to resolve the problem. I have contacted my ISP and as I was able to send an email to myself via their Webmail service they are adamant that the problem is with Windows Live Mail rather than themselves.

Any suggestions as to what is suddenly causing this problem as I am really keen to sort this out as quickly as possible as I am currently in the process of applying for a new job and need to email a number of documents to my new employer as part of the application process?

Thanks in advance for any suggestions/fixes to sort this out.

Andy.