Executable Files not running in WinXP

Hi,

I've got a really serious problem with my system. The description goes like this :

As usual, I ran the Spybot search & destroy software to clean any spyware present in my system. After Spybot had performed the system scan, it displayed the message that

the problems found are fixed. Now, I closed Spybot software and clicked the winamp icon on my desktop. To my surprise I found the follwing error message :

"The file does not have a program associated with it for performing this action. Create an association in the Folder Options control panel."

I didn't understand what the problem was, and tried to open the spybot software to see if there is any spyware. And again I get the same message. Now when I try to open any software installed in my system whether it is winamp, spybot, winzip, system mechanic, or whatever it is(either from the desktop, or from the start menu, or from shortcuts, or from the program folder itself), I get the same error message.

Infact, shortly speaking, none of the executable files of any of the installed software applications in the system can be run.

Now, I tried to run a windows application called regedit and this time I find the error message in a seperate window like this :

"Windows cannot open this file

File : regedit.exe

To open this file, Windows needs to know what progrm created it. Windows can go online to look it up automatically, or you can manually select from a list of programs on your computer.

What do you want to do?

1.) Use the Web service to find the appropriate program.
2.) Select the program from a list. "

It's just not regedit, but even if I try to open any of the default windows applications like mspaint, wordpad, notepad(or whatever windows application it is), the computer shows me the same error message. How the hell can I select a program from the list, when I'm trying to run a program itself ??

So, shorlty speaking, when I try to run an installed software application like winamp, winzip, or system mechanic, I get the first error message(stated above), and if I try to run the windows applications like mspaint, regedit, or notepad, the second message is being displayed.

I'm really getting mad about this , because my Win XP is perfectly updated and all the softwares were rightly working untill I performed this anti-spyware scan after which the above stated problem arose.

Anyone, please help me out !!!!

Please post your sugestions in the forum and please send them to my e-mail too. My e-mail address is : gyrationguy@yahoo.com.

I'll be greatfull to anyone who will help me out solve this problem. Thanq!!!