Editing the registry may really mess up your computer if you do anything wrong.
Makeup a backup copy of your registry on before ever opening a registry editor. Restoring your registry is important if you accidentally delete an entry from your registry that you should not have deleted.
Erunt is the easiest way to back up your registry if using Windows 2000/2003/XP/7/8/10.
To backup a Windows registry without installing extra software:
Press Windows and the letter R on your keyboard to open the run menu. Type regedit in the box to open Windows Registry Editor.
Highlight File, and then highlight and click on Export. Type BackupReg or some similar name in the File name box. Click Save and close the dialog box. This way if you goof and delete something you shouldn't have you can reopen your registry and choose Import and select the saved registration file that you want to restore--later.
Restoring the registry won't fix your problem is you accidentally deleted a file that the registry is looking for. In this case the registry is generating the message that some program is looking for the file you deleted.
If you were lucky and managed to delete enough of the program you were trying to delete and the file causing the problem was named under the company that made the program as opposed to the name of the program in the registry you could try running a registry cleaner utility. Like you tried to do when you were using finder review the list of files carefully before deleting anything.
Attention Window 98 users: When I installed Windows 98 second edition, I found a nifty program listed under Accessories--System Tools, called Microsoft System Information. Under tools this program has two handy utilities.
Registry Checker scans your registry for errors. If no errors are found it gives you the option of backing up your registry.
System File Checker scans your system files looking for corrupt files. When it finds one; it asks you if you want to back up a copy of the file. Then it searches for the original file from your Windows 98 upgrade disk, and copies the good file to your Windows System directory. I used this way back when my original Pentium acted flaky, and was happy with the results.
By carefully following the directions on Registry System Tweaks and Free Utilities for Windows Performance it's possible to fix and optimize with tweaks posted on the Internet. Go slow. Live with a tweak so it's easy to change it back if it makes no difference or your system crashes.
Call It A Day Options left when nothing you do seems to fix your Windows woes.
Smatterings: Windows Maintenance and Optimizing Tips page.