I have downloaded the 7650 video recoreder file to my PC. I have tried on several occasions to send this to my phone via my Yahoo pop3 email. Once downloaded the attachment is not the 'SIS' file that I sent, it is now renamed as 'winmail.dat' I can't open it as the phone says it doesn't support file format!

Anyone got any suggestions?

Change your email program settings on your PC to send messages in plain text format (the winmail.dat thing is could happen with Microsoft Outlook, if you send Rich Text Format messages to a system that doesn't know how to deal with them).