Windows starts in black screen only with cursor and no taskmgr

Hi;

I've faced a real problem here, yesterday after plugging a USB to my laptop, NODE 32 warned about a Parite.A Virus, after that many .exe files got cleaned by Node but some of them got quarantined either. Windows, taskmanager and every necessary things worked fine even after several restart until the last time that upon holding ctrl+shift+esc it said that taskmgr cannot be found. I've restarted the system but this time after the user logon page I get only a black screen with mouse cursor and nothing works. I've tried ctrl+alt+del to access to task manager but by clicking task manager nothing happens. I've also tried pressing shift button several times to access to "ease of access" but it again says control panel not found. Pressing windows key + U also shows not found dialog.

I've tried to repair the system with windows 7 DVD repair option. I've used sfc and some files got corrected but that not changed anything still I got that black screen. I've no restore point either.

It seems that windows works and some programs run behind the scene but it is absolutely useless. Could you please help me? I've several engineer softwares/programs installed on my system that I don't have an access to setup files. I cannot re-install windows in this case. Is there a way so that i can repair system files?

Btw my operating system is windows 7 Ultimate 32bit.

Thanks in advance

Obviously you're infected to the point Win7 can no longer even boot.

Everything that possibly can be done is here for Troubleshooting Windows 7 Failure to Start.

In your case I'd skip to the step to post the infection for specialized help in our Security section, so that they can provide you with the boot disk which can clean it.

I've finally made it works, at least I've managed to recover my desktop, the problem was in userinit.exe file. It had been changed to sth like userinit.exe.vir by Node32. I've renamed it to the previous one and it's wotking now.
Now I face a new problem, upon executing some .exe files (like calc.exe, cmd.exe, adobe.exe etc.) I get an error saying its not a valid Win32 progrem. Any idea what could cause this? Again I guess the exe file is fine but something prevents windows to run it?

Thanks