Reverse soft engineering needed to modify a software using assembly language

I have an old P-1 PC which has a DOS based [login to view URL] software can be installed in that specefic hard disk [login to view URL] checks most probably the physical ID/serial of that hard disk and sets itself up.I tried other hard disks..but it was showing 'this hard disk is not for this software'.Now my that hard disk is having bad sectors.I want to omit the hardware physical serial checking instructions from the software so that it can be installed and run successfully in any [login to view URL] the software checks in two phases...in first phase,it checks during the time of [login to view URL] second,during the time of running the soft after successful [login to view URL] time it checks the specefic HDD and runs it checking is successful. Now i could solve the first checking with some help and successful setup is [login to view URL] during running the soft, second checking i couldn't skip/break. So i want : 1. Successful Running of the software 2. Features of the soft are accessible 3. Compatible with P-4 or higher machines and bootable from CD. The ISO image of the software CD is given in the address attached.. plzz download it from [login to view URL] Quick install procedure after downloading from megashare: - burn ISO to CD - boot CD - choose whatever you want to install - it will start installing and then probably say HDD not good - you are now into nc shell (two blue panels) - in drive D:\ you can run [login to view URL] to install what you choosed - in drive E:\ you have folders of all version - each folder got an [login to view URL] file - just run the file within folder version you want to install..it will be [login to view URL] restart and here the problem starts.....best of luck.