Drop down menus instant-disappear in any web browser

[Q]

This is really odd; on my other computer, no matter what the browser I use, I cannot access drop down menus. This includes both the browser (say bookmarks dropdown) and websites as well (say, selecting a state on a dropdown menu form). They both instantly 'close' again.

I've tried various browsers, updated my Java, ran virus scans and spyware scans to no avail.

Any idea what's going on?

Note, this has been happening the past 3 days, before that all was fine. Also, sometimes the bookmarks dropdown will work, but nothing else.

EDIT: Weird, it did the insta-close on the Win 7 speaker volume as well, so I guess its not just the browsers....

 

[Puppies04]

Couple of suggestions here.. http://www.techpowerup.com/forums/showthread.php?t=51018

 

[VirtualLarry]

keyboard key held down?

 

[FoxFifth]

Left click mouse button in Mouse Properties set to "Double-click" rather than the default "Click"?

 

[Q]

Fixed, it was a problem with the wireless mouse. Using trackpad and everything works.

Odd. Thanks all!

 

[Ketchup]

Is it a Microsoft mouse? Mine had the same issue. There is a fix here:

http://www.fixya.com/support/t1899611-mouse_double_clicks_when_single_click