If the area on the left hand side of the page where you usually log in is blank, it is probably a Flash issue.
Please make sure you have Flash 10 installed. If you already have Flash 10, please go here and move the slider so that you are allotting at least 100KB to storing flash objects. Check the "Allow third party Flash content" and "Store common Flash components" checkboxes. It may also help if you click on "Delete all sites" in the Settings Manager, which clears your Flash cache.