We have this week migrated servers to 2007 from 2003. This has pretty much gone smoothly - however an interesting problem has arisen. When PDFs and JPEGs and other file attachements are sent from Outlook clients to external clients they are stripped down to 1kb and are unreadable by those external clients. Internal client receive the full document no problem. I cannot work ou when the problem is. No limits have been set up as far a I can see - in terms of file size. An mailbox limits are no where near at capacity. Bit lost hope some one has an idea of what is causing this!