The pirated copies of Windows 7 that are circulating in bitorrent tracking sites have Trojan in them.
“Just a warning for anyone downloading the new RC builds of windows 7. Quiet [sic] a lot of the downloads have a trojan inbedded [sic] in the setup EXE. The Setup EXE is actually a container, it appears to be a self-extracting EXE. There are 2 files inside, Setup.exe and codec.exe,” said a user in Neowin.net’s forum.
The codec.exe is identified as a Trojan by the user’s antivirus software.
Source: COMPUTERWORLD

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MD5
8867c13330f56a93944bcd46dcd73590
SHA1
7D1F486CA569EFFFFB719CFB48355BB7BF499712
ooops! I forgot to mention that those values above are for the x86 version.
x64 SHA1
FC867FE1AB2E0A9796F9E4D155B44EA6998F4874
Why does anybody with a brain bother with the torrents when Microsoft is allowing free downloads from their own servers? Is getting a Win7 RC a few weeks early really worth that kind of risk? Bragging rights can come awfully expensive if you don’t think before you download.