error when purchasing online course

[bingfuli]

When I purchase the online course, there is always an error "Error-20511 processing request. " after I press the "process the order now" button on the last but one step. Is there anyone who has the same problem as me? Is there anyone who can tell me how can I do? Thanks!!!

[Kongo]

I had trouble making a purchase yesterday on their site for something else... may be their payment system is down

[campbell]

It would probably be best if you contact CAS directly, btw.