When you try to run an application you receive an error saying make sure you typed the name correctly.  This can often be resolved by repairing the registry entry as shown below:

This is the manual method, but you could use RKILL.

1. Click Start, and then click Run.

2. Type "command.com" , and then press Enter. (A DOS window opens.)

3. Type the following:

         "cd\"

         "cd \windows"

    Press Enter after typing each one.

4. Type copy "regedit.exe regedit.com" and then press Enter.

5. Type "start regedit.com" and then press Enter. 

6. Navigate to and select the key:

    HKEY_CLASSES_ROOT\exefile\shell\open\command

7. In the right pane, double-click the (Default) value.

8. Delete the current value data, and then type:

     "%1" %*

 Tip: Type the characters: quote-percent-one-quote-space-percent-asterisk.

9. Close Regedit utility.

The above information can be found at http://support.microsoft.com/kb/555067

After resolving this registry fault you should run a full virus scan with your preferred Anti-Virus software.