iTunes works fine until I attempt to go to the Store, then it crashes. From then on, Windows will NOT allow iTunes to operate.

I am using Windows 8.1. iTunes works as always until I attempt to open the iTunes Store. It crashes at that point, and from then on, iTunes will not open. I have attempted to re-load iTunes repeatedly, as well as loading older versions of iTunes. I have explained this to HP Support until I am ready to scream, yet the only advice they can give me is to either re-load iTunes, or re-install Windows 8.