vpn and exe's

I'm attempting to sync a folder up that goes through a VPN across the country. Text files, pdfs, ppts, and basically every filetype I had at hand would go through it but when I try to send across an .exe file it sticks as a toucan.tmp file. I've even tried to rename it to what it should have been. Is their a known problem with exe's and vpns? I looked through a good chunk of the forum and didn't see it but I may have just over looked it. Thanks