Do you get an error message when you try to send or receive? If so,
right-click on your error message, copy, then paste it into a reply here.
We can't do much troubleshooting without the complete error message.
Don't go changing ports unless your mail provider supports it.
The 0x80004005 error has been associated in the past with corruption
on the server. Log in to webmail (https://webmail.blueyonder.co.uk ),
Then clean out all the folders in your webmail. If you want to save
any messages, create a new folder and move those messages to the
new folder. Empty the spam and thrash folders also. Close webmail,
then try Windows Mail again.
If no improvement, Which antivirus are you running? Some of them
cause problems with Windows Mail over time.