> I don't know how cmpro reckons the "data" is valid (ie. able to decompress,
> check the crc and not report a problem) when I have tried a "Test" and also the
> "Extract" in WinRar and both options give me a CRC error and also 7z.exe reports
> an error...here's the output from a CMD prompt:


Because cmpro isn't winrar and not 7z. cmpro uses the sdk to access the data and uses the 7z sdk again to decompress it and rechecks the checksums. Since the SDK doesn't return an error code, the sdk is either wrong or the data is ok.


> Does the "decompress and check CRC" actually decompress or does it just use the
> CRC value packed into the header?

It decompresses the data to memory, calculates the checksums over the decompressed data and compares it against the one stored in the datfile. Not against the one in the header, so maybe in your case the header is just wrong, while the data isn't.


> I can email you the files but 1894 is ~24mb and 1936 is ~15mb.

You can send me the smaller one to roman*dot*scherzer*at*gmail*dot*com


Roman Scherzer