One thing that always causes hassle for us as an e-mail services provider is the use of double extension file names attached to e-mails. e.g. annualreport.doc.pdf – this looks harmless, however in file naming terms it’s wrong. A filename should be comprised of a meaningfull name and it’s extension. I don’t know if this is a user issue or an application issue, but I suspect a bit of both.
If you insist on using double file extensions because your application makes them that way, then change the application. Or even better rename the file before sending. You have to save it anyway, correct? Well then, save the file with the proper file extension, then e-mail that file to the intended recipient.
The main reason for this slightly ranty post is that our mail scanning software catches all double extension attachments and treats them as an attempt to send a virus. Now it doesn’t delete them, or do anything funky with them, it sends the original message with the attachment replaced with a warning text file letting us know what server and the location to the e-mail in the quarantine so we can release it for you. It does this as a lot of traditional viruses used to send themselves from an infected users pc to everyone in their address book as an attachment with a name of something like .doc.com or .doc.exe and it would infect the end users pc.
I’ve considered removing this restriction a few times. But the pedant in me doesn’t let me. Please just use common sense and use proper file extension naming, for the sake of everyone.