May I very strongly point out that using decompressors (unpackers) for EXE's can be very dangerous if you don't know what you're doing!
Especially with files which have been compressed by commercial packers. Because to properly unpack them you need to either have a license or a password or something. And in many cases you simply can not unpack it just like that.
What those unpackers for commerical packers do is actually executing the packed EXE to get to the unpacked image in memory (a file is always runned unpacked in Windows internally). And there lies the extremely big danger! The files _are_ executed and thus malicious stuff which might exist in those files _is_ executed. Thus this is _not_ like unpacking a RAR file or ZIP file where nothing is executed.
'Generic unpackers' or 'generic methods' and those kind of things found in unpackers (like PEiD) should _only_ be used if you know _exactly_ what you're doing and have a extremely good knowledge of how such things work and _exactly_ what the packed files might do when executed.
Also note that unpacked versions of executeables quite often do not run properly anymore and might render errors (even if you don't see anything out of the ordinary at first sight!!!). They also quite often do not result in a proper EXE layout.
Many unpackers also say they unpacked a file, yet fail to do it correctly.
Bottom line: Do not use such tools if you do not know what you're doing or if you don't have the knowledge of how such things works. (at least not on your main PC, do whatever you want on a test PC of course
).
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