Hi!
I am working hard to create Bitzi tickets for the innumerable fake files on the various P2P networks -- eDonkey, G1 and G2. The fake, malicious files are too numerous for me to keep up with, and many of the fake files have no Bitzi ticket yet, so you can't depend on Bitzi to have an entry for the particular file you want to check. By all means, do check Bitzi, but don't rely on it because there are at least as many malicious files I haven't tested yet as there are files I have rated.
If you have doubts about a file, or even if you don't have doubts, one thing to do is have the file checked for viruses and malware. Visit
http://www.virustotal.com/, and upload the file to their free virus-checking service. That won't absolutely guarantee the file's purity, but it will be a good start. In some cases the file will prompt you to download an update to Windows Media Player or QuickTime -- if it does that, then it's probably a fake file trying to infect you: Don't download the "update," simply close your browser from the taskbar! Right-click on your browser's entry on the Windows taskbar, then click "close." That will close your browser and make you lose your place on the Internet, but that's better than being infected, right?
Bitzi is a great service, but those of us trying to identify all the bad files are behind in our work, sorry! It is an enormous job.
Yours sincerely,
Richard