Here are a few questions that will help us find, duplicate, and hopefully resolve the problem:
Did you receive any error messages (if yes, what were they)?
What were the exact steps, pages, clicks, etc. you tried? Please be as specific as possible so we can copy exactly what you did.
Which browser and version are you using (eg., Firefox 3.5.9, Internet Explorer 7, etc.)
Have you tried a different browser?