500 Internal Server Error

My whole website is down.
I've got more than 40 emails during the night with this message:
Cannot open /var/log/sa/sa30: No such file or directory ( sender Cron Deamon )

If i visit our site i get this message:

Internal Server Error

The server encountered an internal error or misconfiguration and was unable to complete your request.

Please contact the server administrator to inform of the time the error occurred and of anything you might have done that may have caused the error.

More information about this error may be available in the server error log.

Is this a Boonex error or a server error? If i go to the server i saw nothing out of the ordinary.

Well i would check with the host. Because the first error the path of var/log is definitely a path on the server, not a dolphin folder.

Yes, i thought so...