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Dwood
June 13th, 2010, 10:46 PM
So a while back I tried debugging some applications with odbg on a win xp 64 bit when I was dual booting 32 and 64, I noticed that in odbg that the addresses double and the instructions are different... Now that I'm on Win 7 (64 bit only) has that changed at all? Also, what about possible solutions for debugging apps (say, Halo CE for instance) so they don't read the memory wrong?

I didn't try this at the time but does simply setting the compatibility mode to, say, winXP sp2 (or whatever) work?
Cojafoji
June 14th, 2010, 11:24 AM
I assume you're talking about ollydbg? The guy hasn't released a 32-bit version of the program, so I'm gonna venture a guess and say no.

From the site:



Last update: June 04, 2010 - final release (corrected). Here it is. (http://www.ollydbg.de/odbg200.zip) <---2.00
And once again: no, this version does not work under Win64!

Version 2.01 will finally work under 64-bit Windows. Probably I will start developing 64-bit OllyDbg, but this depends on my free time.
Kornman00
June 14th, 2010, 03:49 PM
Pointers are the size of a word (http://en.wikipedia.org/wiki/Word_%28computing%29) on the processor. 32-bit processor word = 32-bits, 64-bit processor word = 64-bits. That's why you see your addresses "doubling". Registers (among other things (http://en.wikipedia.org/wiki/Word_%28computing%29#Uses_of_words)) are also same size as a processor word. The old 32-bit instructions set can't operate on 64-bit data so an added set of instructions had to be made.
CrAsHOvErRide
June 24th, 2010, 04:16 PM
To complete this thread..it is possible to use OllyDbg in a x64 environment (get OllyAdvance plugin for this) but not for debugging x64 applications.
Dwood
June 25th, 2010, 02:34 AM
To complete this thread..it is possible to use OllyDbg in a x64 environment (get OllyAdvance plugin for this) but not for debugging x64 applications.

No. that's what I was talking about in the 1st post, even the 32bit apps aren't read properly.
CrAsHOvErRide
June 26th, 2010, 10:22 AM
Are you using the plug in? It is necessary to run Olly in a x64 environment (single step issue).
Dwood
June 27th, 2010, 01:59 AM
Are you using the plug in? It is necessary to run Olly in a x64 environment (single step issue).

Sorry I read your post wrong. also is: http://www.openrce.org/downloads/details/241/Olly_Advanced

what you're talking about?
CrAsHOvErRide
June 27th, 2010, 07:30 AM
Yes.