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I'm searching some info about this file. It was recovered from a failed HD, with Ontrack EasyRecovery. The file extension may not be accurate. I tried with TrID (I'm the developer), and based on the firsts 4 bytes it's identified as a "Windows Program Manager Group", but I'm not convinced it's right.

Anyone is familiar with this kind of filetypes?

File extension: GRP
File size: 902KB

0000: 50 4D 43 43 44 3B 32 55 F1 FD FF FE FF FA F6 FC  PMCCD;2U........
0010: FC FF FF FC FD FF F9 FD A4 34 24 41 37 4E 4F 55  .........4$A7NOU
0020: 4F 4A 4F 47 3A 06 38 37 1D 18 32 9E FD FD FF FF  OJOG:.87..2.....
0030: FC 1C FF FE FA FF FE FF FF F8 C5 7A 26 28 3E 39  ...........z&(>9
0040: 50 3C 4C 4C 4E 56 4D 4D 3A 37 2B 1F 59 D6 FD FE  P<LLNVMM:7+.Y...
0050: FF 1A F6 FC FF FF F9 FF FB D6 36 1C 30 46 4F 4F  ..........6.0FOO
0060: 50 47 4B 44 3D 25 36 BC F6 FE FB FC FA F1 FF 00  PGKD=%6.........
0070: FB FE FF 23 84 3A 47 52 4F 54 4B 4A 46 43 41 30  ...#.:GROTKJFCA0
0080: 39 98 FC F4 FD F7 FC FD FA FD FE FE FF 61 1C 1E  9............a..
0090: 38 3F 4B 4C 48 49 4B 4D 06 4A 32 3E 31 77 C9 FC  8?KLHIKM.J2>1w..
00A0: FE FE FD FF FF FE 20 FC FF FF F3 FB FF C0 64 37  ...... .......d7
00B0: 15 29 34 4C 45 4A 4C 57 39 41 2D 14 36 BF FC FB  .)4LEJLW9A-.6...
00C0: FE FB FF FF FE FA FC FC FE FF 34 FD 8B 0A 18 35  ..........4....5
00D0: 43 45 44 4A 47 46 4E 54 4C 46 3C 49 37 50 55 3E  CEDJGFNTLF<I7PU>
00E0: 7F CC EE F9 FF FC F9 FF FB FD FA F8 FF F9 D7 69  ...............i
00F0: 38 21 3B 3D 44 48 44 4D 49 4C 44 40 32 1B 36 A1  8!;=DHDMILD@2.6.
share|improve this question
It seems reasonable to assume that this is, in fact, a Windows Program Manager Group file. What makes you doubt it? – Oliver Salzburg Jun 18 '12 at 16:12
Just that it would be something from the Windows 3.x era, I think, and it doesn't seems much probable to find it on a modern system. Of course it could also be just a block of pseudo random data collected by the recovery tool, that just happens to start with "PMCC". – Mark0 Jun 18 '12 at 16:32
Ah, well, yes, there is that ;) On the other hand, the file extension even fits the magic bytes. Maybe the file came with an application that had some legacy 3.1 support or something like that. I would assume the best clues regarding the origin of the file are the file name, the containing folder and the files next to it. Or copying it into a 3.1 VM and checking it ;) – Oliver Salzburg Jun 18 '12 at 16:40
I'm sure that all (newer than 3.x) versions of Windows support this format as well, so it's possible that older software was installed that created groups, and Explorer converted these to standard Start Menu items. – user3463 Jun 18 '12 at 17:28
OK, found a real GRP file from a Win 3.1 installation. The file looks immediately very different, with clear references to paths, descriptions, etc. It's definitely not a Program Manager Group. I'm inclined to think that this is just some random data. P.S. Is right to post this here as a comment, or would it be better to post it as an answer, with an hexdump of the real GRP file, as a reference? Thanks. – Mark0 Jun 18 '12 at 20:35

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