Thanks for the reply.
I am reporting them as attachments via my forwarding address with SpamSource v3.11.594 in Outlook 2003. Always done so (2 years now) and no problems with configuration until switch to broadband with Tiscali from UK Online dial-up. The reports are being sent via the default email account and no bounce message is returned, nothing is at all.
I have 3 email addresses, 2 using tiscali servers (one being an old LineOne account) and the ukonline account.
smtp.tiscali.co.uk is the outgoing server I use now for all accounts in Outlook and I ticked every option for the Tiscali mail servers on the spamcop mailhost setup page.
I am at a loss here as I can send an receive emails without problems on all accounts.