Please help me i did something really stupid!

I was trying to fix a problem and was following some instructions early in the morning when I accidentally deleted the wrong key in Registry Editor, HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\ and now my computer is really messed up can anyone please help me fix it?

 

If you had done any backup of your computer system before this incident happened using any backup tools, then you're in luck.
If you did not, then I'll classify your case as a corrupt Windows registry issue. You did not state which OS you are using.
I assume that you are running Windows XP.
Read this: http://support.microsoft.com/kb/307545/
Please be more careful next time when editing the registry.

 

Did you already try at a command prompt: scanreg /fix

 

If you can get to the bootup Safe Mode Menu, you can try the
Last Good Configuration option.

Or, if you can boot into Safe Mode, you can use System Restore and see if you have a checkpoint prior to your problem.

Start/Programs/Accessories/System Tools/System Restore

Once you get your system back to normal again, you might want to consider a program such as

• ERUNT to make quality backups of your registry.
  http://206.128.27.142/ubb/ultimatebb.php?/ubb/get_topic/f/9/t/000145.html
  
• ....and a program such as Acronis True Image 9 to make quality backups of your entire system.

 

Sorry I didn;t mention the OS earlier, and yes it is Windows XP. Im using a Toshiba Laptop and none of the sudjestions you guys gave me worked, sadly. I tried System Restore, but it has an error and I cannot use that either. My Programs in Start Menu are gone, my Search function in Start Menu is gone, and many programs I try to open do not work. Even my Battery Power options. I tried a program to fix my registry and that didnt solve my problem either. I know im pretty much screwed cause i dont have a backup and i know i should have done that, but is there a manual way to replace the keys i deleted? I know replacing them all is rediculous to do it manually but i cant think of any other way.

 

Maybe this works :
1. Insert the Windows Installation CD and reboot
2. Instead of choosing installing, choose the repair option.
Hope this helps.

High time for you to think of a backup solution.

 

There's another thing to check: look in the folder "C:\WINDOWS\repair". Is there a file in there named simply "SOFTWARE"?

If so, and the date on it is acceptably recent, consider having a look at http://support.microsoft.com/default.aspx?scid=kb;en-us;307545 It depends on how knowledgeable or comfortable you are in following Microsoft KB registry repair procedures as to whether it'll be useful to you or not.

I or others can probably answer questions you may have on the Microsoft procedure but, depending on your comfort level with this, you may well be better off just doing the repair install as Erik suggested.