Hi,
If you use Spybot S&D, open Spybot in Advanced mode and check the Immunize
settings. You may have placed this restriction inadvertently.
If not ... go to Dealing with Unwanted Spyware and Parasites: http://mvps.org/winhelp2002/unwanted.htm Scroll down to
"Various Registry Fixes" You will find a REG file to unlock this.
Next (same page) check for parasites and other malware which may have caused
this, if Spybot didn't.