Practice Exam Error

I've tried accessing the practice exam dashboard with the links under both the OVERIVIEW and EXAMS tab of my account. I just get an Error page, with no other explanation. I've tried using different browsers and even on a different computer. My colleague seems to be able to access the practice exams just fine. This may be specific to my account. Has anyone had this issue? How do I resolve it? I need to be able to do the practice exams. 

Thanks