Bad request after bad request

For the past week or so I have been getting “Bad request” when I click on a thread or a new page or just about anything on this site. At first it was just occasionally, now it is about half the time that my clicks end up with a “Bad request.”

Why?

I have restarted my computer multiple times.

I am using Safari.

I had that on my Kindle Fire. Amazon had me clear cache and cookies - unfortunately it cleared all my bookmarks also, but it worked. Not sure that will help you-hopefully a computer expert will answer soon. I hate being without CoTH!