As long as you download WPE from the maker (
[Only registered and activated users can see links. Click Here To Register...]) then it shouldn't have a virus in it. The reason why it says that it has a trojan is because it is a Winsock based program, which trojans work on. But it is not a trojan. Just make sure your antivirus is off when you extract is, since I had a problem extracting while my antivirus was on, disabled it, and fixed the problem.