BleepingComputer.com: Problem while upgrade windows XP Pro

ok here is my problem, i had a PC with lot of viruses in my company, we did some cleaning up with eset cleaning utility and it apperars that it succeeded however registry and soe stuff remained corrupted, so i tried to use upgrade with an my windows XP Pro CD, everything started fine, then at some point, it show me this error and the upgrade stop !!!
"the signature for windows xp professional upgrade is invalid. the error code is 426"
Now i don't want to upgrade anymore, howveer i am stuck ina loop of infinite "upgrade setup start...then stop with error... the restart" and i don't have any option to quit.

Please i need help, what can i do, i don't have a recovery console on that PC, is there a way to install it now using my XP CD ? how can i fix the boot, i want to start to the bad XP, it is working at least

Thanks

One more thing, my original problem was because i didn't had the same version of XP that was installed on the PC originally, so when i boot from CD i don't have an option for repair or recover, there is only automatic recover or something similar. Is there some way to install a new XP, then change the boot to let it boot from the old XP that exists already untouched on my C: partition (since the windows folder in this case will be windows1), i am not fluent with this stuff, i need to know if the old registry is still somewhere on the disk, because i know my files will be there.

Thanks

mediumkuriboh, on Nov 19 2008, 08:15 PM, said:

Another idea is to put the Hard disk in my another PC and read and fix the boot.ini in it, does this make any sense ? can i plug 2 hard disks to one PC ? how the PC will differ between C and D, and the other C and D ? And can i read the content in the other disk ?

Thanks

I suggest...a clean install.

Clean Install Procedure with Illustrative Screen Captures - http://www.theeldergeek.com/xp_home_install_-_graphic.htm

Louis

hamluis, on Nov 19 2008, 09:35 PM, said:

No there is an application on that PC and it is not backed up, if only i can make it boot in windows instead of windows setup that would be great, i succeeded to access the Hard disk from another PC, but i don't know what should i change to let it run in XP and not XP setup, any idea what to do. Please i need urgent help.

Thanks