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  #1  
Old 12-25-2014, 05:21 PM
melwarren melwarren is offline
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Posts: 11
Default Editing an exe file

I'm trying to edit an exe file to removing the call to a hardlock dongle. I am working in softice. I have found the jump that I would like to change.
10F7:4C86 7404 JZ 4C8C
10F7:4C88 33CO XOR AX,AX
10F7:4C8A C9 LEAVE
10F7:4C8B CB RETF
10F7:4C8C B80100 MOV AX,OOO1

I wound like to change JZ to JNZ. I know that I need to change the 74 to 75, but how do I find that line of code in a hex editor or W32Dasm. It doesn't look the same when you disassemble with W32Dasm as softice. I have been searching for the answer but I don't know ask the question.
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  #2  
Old 12-26-2014, 05:38 AM
user1 user1 is offline
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Smile ?

U need to undongle it and use a dll to return right values to main exe.
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  #3  
Old 12-26-2014, 01:55 PM
nodongle nodongle is offline
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Default

Simply find these bytes in the file:
74 04 33 C0 C9 CB B8 01 00
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  #4  
Old 12-30-2014, 11:10 AM
yogi_saw yogi_saw is offline
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Posts: 533
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use Olly to debug it can change and save your new instructions.... for this case it may not be as simple as u thought.... search this forum for more info....user1 responded right
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  #5  
Old 12-31-2014, 07:54 PM
melwarren melwarren is offline
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thanks for the reply. Olly only works for 32bit programs. This is a older 16bit. I will continue to work on it.
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  #6  
Old 01-01-2015, 03:10 AM
melwarren melwarren is offline
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I have changed every 7404 to 7504 one at a time but none changed the value I was looking for. I think it is time to give up. Thanks for the help everyone.
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