Virus scan of the main files of the client, that launch it. This is just a scan of the main client, not of the bin or data folders.
I had a professional developer of mine take a look at the file. His virus scanner alerted him immediately, so he decided to investigate. After unpacking just a few files, the first line in it was "explorer.exe". Meaning it does something with explorer.exe [main part of windows] behind your back. This is also the starting line for many other viruses and trojans.
The above link is a scan on these files. Many virus scanners don't pick it up, but some of the good ones do. Some very unused virus scanners do as well because they scan for things many others don't.
Anyways yea... delete the client. Shred the files. W/e. Get this horrid **** heap of a virus off your computer.