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w_a_r_1
January 26th, 2011, 00:04
Hi,

normally few programs have restrictions like you can execute a program only once at one time. you cant open multiple instances of the same program. so is there any way of opening multiple instances of same program?? any api hooking technique?

radix
January 26th, 2011, 08:42
Hi,

Windows itself does not limit concurrently running instances, the application has to do it. The recommended way is to use a mutex (CreateMutex), but some programs may use file locks or other shared resources to detect that another instance is running (and then terminate itself). A simple way to check that is to use Process Explorer (SysInternals/Microsoft) and look at the open handles - you can even close handles to see, if that's the one that blocks more instances. Applications allow only single instances for a reason - most of the time because of lacking synchronization features. So you could damage some data if you force a second instance running.

radix

disavowed
January 26th, 2011, 09:40
Here's an analysis walkthrough for Outlook:
Part 1: http://malwareanalysis.com/CommunityServer/blogs/geffner/archive/2007/08/10/234.aspx
Part 2: http://malwareanalysis.com/CommunityServer/blogs/geffner/archive/2007/08/31/359.aspx

w_a_r_1
January 28th, 2011, 00:07
thanks radix and disavowed I like it disavowed you are still helping others