Hi pike2spike,
Check your firewall settings. In particular, check that the application 'WinMail.exe' is allowed network access. Your ISP, blueyonder, is now part of Virgin Media, so here are a couple of links that might help you. The first is to inform Virgin Media of your previous ISP, i.e. blueyonder. The second, if you are still having problems, is to the relevant login page for the web version of your mail account.
Dwarf
Connecting you - Virgin Media
https://webmail.blueyonder.co.uk/