Additional Details
Packed:W32/MysticCompressor.gen!A is a generic detection for a packer called "Mystic Compressor", which is commonly used by the
ZBot/Zeus trojan (password stealer programs) and
rogue antispyware programs (such as XPAntivirus).
Malware authors use packers, or file compressor programs, to compress their malware and thwart security programs attempting to scan, debug, emulate or unpack the compressed file as part of their normal security procedures.
About generic detectionsUnlike signature or single-file detections, a Generic Detection does not identify a unique or individual malicious program. Instead, a Generic Detection looks for broadly applicable code or behavior characteristics that indicate a file as potentially malicious, so that a single Generic Detection can efficiently identify dozens, or even hundreds of malware.