Well, I need to practice my english, so:
1) I recommend you to use Olly 1.10 and StrongOD plugin. Also, always tray to unpack using Windows XP SP3 (a Virtual Machine is pretty handy for this).
2) In this case, OEP is at 702742h. To get to the OEP:
- At the EP (C1F400) put a BPM in the .text section and hit F9. When Olly stops, you'll be at C33C95:
00C33C95 281F SUB BYTE PTR DS:[EDI],BL
00C33C97 50 PUSH EAX
00C33C98 8B85 F3D24200 MOV EAX,DWORD PTR SS:[EBP+0x42D2F3]
00C33C9E 3207 XOR AL,BYTE PTR DS:[EDI]
00C33CA0 D1C0 ROL EAX,1
00C33CA2 8985 F3D24200 MOV DWORD PTR SS:[EBP+0x42D2F3],EAX
00C33CA8 58 POP EAX
00C33CA9 47 INC EDI
00C33CAA 59 POP ECX
00C33CAB E2 02 LOOPD SHORT 3DSimED3.00C33CAF
00C33CAD EB 05 JMP SHORT 3DSimED3.00C33CB4
00C33CAF ^ E9 21FFFFFF JMP 3DSimED3.00C33BD5
00C33CB4 C3 RETN
If you watch the code, you'll see that the LOOP at 00C33CAB goes to the JMP at 00C33CAF and that JMP goes up. BUT the JMP between both (00C33CAD) goes to the RETN.
Now, Put a BP on that RETN (00C33CB4) and hit F9. When Olly stops, put a BPM in the .text section and hit F9. When Olly stops, you'll be at OEP:
00702742 . E8 26410100 CALL 3DSimED3.0071686D
Now you can dump and rebuild IAT with ImpRec. You'll have 4 bad entries in the IAT. The first is ExitProcess (the same as the tutorial).
The other 3 are used by the program to comunicate with the packer. You'll have to wach what happens in each of those 3 (what registers are modified and what is modified in the stack).
In fact, only 2 functions are important. Both MUST return 0 in EAX, but they also return data in the stack, so be careful with that.
And that should be enough to remove the packer...
Cheers!
EDIT:I forgot to tell you to check all the exceptions, so they are passed to the packer!
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