I, too, have been suffering from exactly the same problem and have tried several things to resolve the problem - installed Google Chrome, uninstalled Google Chrome, ran Microsoft Fix 50544, etc. I eventually decided that I would try taking IE off completely and running Firefox for a while and see if that resolved the issue of not being able to use hyperlinks. Instead of taking IE straight off I actually reverted from IE9 back to IE8 and, guess what, all of my hyperlinks work again. Don't promise that this will work for everyone but if you have "upgraded" to IE9 and are encountering this problem it might be worth a try. You can put IE9 back again easily enough if you want to.