Start up problem in Win 7 due to installing Win 8 themes

Hi,

I have tried to install win 8 themes in my Win 7 home premium. Few DLL changes were suggested there. After making those instructed changes, it was required to restart the system. Before that it was instructed to disable UAC. I forgot to disable UAC and restarted my laptop.

Now I am seeing welcome screen without displaying logon window. And now I am not able to logon in the system any more. I am struck here.

We have removed all passwords using bios. But still system is struck in the same screen. I am not able to get into the system in any way including command prompt.

I have some critical data in my C drive.

Anyone of you please help me out to get me out of this trouble. I want to save my data.

And system is showing no error message or crash message.

Thanks in Advance.

Critical data? Have you been doing backups? How critical could it be?

Can you boot into safe mode (F8)?

Do you have the win 7 dvd?

It is having my project related data, critical enough. In safe mode also system is struck with same screen. I am able to bypass logon screen. Logon window is not displaying to enter credentials. I have removed all passwords also using bios setting. still it is struck with the same screen.

Yes I have win 7 DVD..

Srry ... I am not able to bypass logon screen in anyway.

Now using win7 dvd I can access my command prompt. I have saved my data also ... still i m thinking not to reinstall windows in my lap. Now is there any way to correct my startup using command prompt.

How did you solve the problem, or did you?

Yes I have solved my problem.
What I have done is this --
1. Win 7 DVD, I used this DVD to boot my system.
2. Selected command prompt as recovery tool.
3. Moved all of my critical data from C drive to D drive.
4. Since I knew the names of DLL's I have changed and I was having the original DLL's with name changed.
5. Replaced those DLL's by original one.
6. Rebooted my system using Hard Disk OS.

Work fine.

Thanks Guys.

Good work, gattu!