START Button, with Left Click, gives NO RESPONSE

Re: Windows XP Pro with SP2 and all updates applied thru February, 2008.


Everything works perfectly until something happens that causes the following
problem:

(1) I left click the START button and I get no response. Nothing. That is
the problem.
(2) I right click the START button and I get the normal menu. It works.
(3) I am using the Classic Menu View. It has always worked just fine for
years.
(4) If I switch from Classic Menu View to Start View, left click on START
button works.
(5) When I reboot Windows XP, the START button is fine again, unless it
mysteriously stops responding!

I have never had this problem before. Also, its not a guarantee it will
happed every time I boot up. The mouse and its buttons are normal. Left is
left, right is right. I am wondering if my February Windows XP update might
have caused this to happen but I do not have any proof. However, it
definitely started happening in February.

Any Comments would be helpful.