Win 7 does not launch after installing new software

Hi,

I have recently installed application on Windows 7. It wanted me to restart system. I have restarted computer and I cannot launch it. At the moment when my computer restarts, it enters start screen (not the one with Windows logo, but the one from which you can request access to BIOS settings) and restarts again. And so on - restarts, tries to launch (no Windows logo), restarts again etc.

I have tried to launch Windows from the disc I received when I bought Windows and choose repair. There were several options - like restoring to last restore point and some others. Unfortunately, not even a single one worked. It looks like installer cannot see correct installation of Windows on the computer. I don't know what happened - maybe the software destroyed MBR. Or maybe it destroyed crucial files in Win OS.

What can I do? Even if I launch computer from some Live CD - I can only check if partitions C and D exists, those that previously existed. And even in that case I will not know what to look for in partition with OS or how to check if MBR was not destroyed.

Thanks for suggestions in advance!

Hi, it was some app to break passwords in archives. I have created archive long time ago and forgot password to it so I wanted to break it with brute force method. (There were also two new drivers I have installed at the same time with this app, before restarting system).

Hi, not exactly. Problem with archive to which I forgot the password is not the issue now because I cannot launch Windows OS at all. My Win OS was destroyed by one of the applications I installed (either password breaker or one of the drivers). I cannot launch Windows at all and repairing it with disc with Windows OS installer (in repair mode, not install mode) does not work - it says that no valid install of Windows is present in the computer. (I have some photos of what appears on the screen so I may write the exact error messages from Win OS repairing failure if you want to). Windows OS itself was not password protected, it was ordinary installation of the system.

Just before installing that app and these two new drivers I have created system restore point but Windows installer from CD in repair mode cannot use that restore point as it cannot find Windows OS on my computer at all. I would prefer not to be forced to reinstall Windows OS because it took me really much time to correctly install all the drivers. (This is old computer and CD with drivers was already lost. Apps like Driver Easy or Driver Identifier could not find some drivers so it was long way to make the system work correctly). I would rather like to fix current installation of Win OS.