Well, here it comes :].
1.
Goto Virustotal (VirusTotal - Free Online Virus, Malware and URL Scanner)
2.
Press Submit a URL.
3.
Copy the download you want to scan. (to find the downloads link right-click the attatchment file :])
4.
Well, press the "Submit a URL" button, and you done!
Please say thanks if this helped ;].