Thanks Lowell for your help with this. I have just awarded myself the Moron of the Day award. As I have Windows Vista on my machine, I had set my SQL mail profile to use a server e-mail account, on which the SMTP mail message size limit was set to 2 MB. I have changed it to 25 MB, and now large attachments are coming through without any problems. Your help saved me a lot of time and frustration, so many thanks to you.