Regardless if I use my laptop or PC, Firefox or IE, I keep getting this. I rather ask here what's wrong then with the customer's provider....
Internal Server Error
The server encountered an internal error or misconfiguration and was unable to complete your request.
Please contact the server administrator, tech-ops@XxXxX.nl
and inform them of the time the error occurred, and anything you might have done that may have caused the error.
More information about this error may be available in the server error log.