Hi,

Heaps of files being shared on the network are infected. You need to be especially careful with zip, rar & exe files

Check file sizes before you download - if the file looks very small (say under 2000 KB) then chances are that it's a bad file.
Check files with Bitzi before download - if other users have rated the file then you'll get some idea of whether it's ok: How to use Bitzi Web Lookup .. & How to use Magnet Links & Direct Connect/Browse/Chat

Make sure that you're using a good antivirus (AV) program. Keep it updated & scan every file that you download with your AV program, before you open the file!!
Virus thread: Typical virus spam file sizes - Make a note of them (click on blue link to see)

* WARNING: Viruses on network you should be aware of ! *


Do you have an administrator account in Vista? If you're sure that you want to open the file, you might need to right click > run as administrator.
Sorry, I'm not a Vista user... that's about all the advice I can give you