You got a file from a untrusted source and want be sure (as much as possible) its not a virus?
You made a new program and want to check if any of the most popular Anti-Virus programs will reject it?
Use the
Virus-Total - File-Scan (http://www.virustotal.com/)
If necessary add the site to the "trusted zone" in your Internet Explorer.
Virus-Total will upload your file and check it using the most popular Anti-Virus Tools.
Thank you that sounds like a very useful link and find, thanks again!