I admit that I visited computer-related Corporation X's website a few times and sent in its feedback form some words which could have classified me as their least favorite person. Anyway, the last time that I did this, when I clicked the "Submit" button, the page verifying that the feedback was received came up with black patches on it. Although I could shake the black patches after a little surfing, I had to reinstall my browser the next day, because it was as dead as a doornail. Do you think that there could have been some sabotaging of my computer, incompatibility of software, or God knows what? I am thinking the worst, but I calm down, dump my imagination, and prefer to believe in the "God knows what" choice.

Hmmmm Sounds to me like you were IP blocked
Hugh may be able to tell you more about what happens if you try to access an account that has you blocked ?