Emails not sending from one of my accounts, am receiving emails though).

Hi everyone,

I use Windows Live Mail (sort of looks like outlook) on my computer.

I have several email accounts which are all used for business purposes.

There have been no issues with any accounts in the past however suddenly one of my accounts is not sending any emails.

It will receive mail just not send.

When I push the send/ receive button the following comes up:

"An unknown error has occurred. Subject 'TEST' Server: 'mail.discoveryfishing.com' Windows Live Mail Error ID: 0x800CCC0B Protocol: SMTP Port: 25 Secure(SSL): No"

What do I do? How do I get the email working again? This has been going on for a couple of months now.