If you are having trouble logging in, please try these three fixes first, before anything else
1. Clear your Browser’s cache http://www.wikihow.com/Clear-Your-Browser’s-Cache
2. Try another Browser (sometimes add-ins can interfere)
3. Clear your Java cache, go to control panel – switch to classic view if you are in category view, then open the Java applet. At the bottom where it says temporary internet files, click settings and then delete (make sure both boxes are checked). Now try again and if you have time, reply here whether it worked for you or not for the benefit of others with this problem.