I have exactly the same problem. It occured when I installed Mcafee Internet Suite. I've spent hours on line with Mcafee. Even talked to a young lady in India for hours. They have some kind of glitch. But, I can't convince them.
Contact Mcafee and tell them of the problem. You can give my name also. Ki Moody. info@TEXMOOD.com 214-221-0867