My b2evolution Version: 2.x

What does the following message mean?

"Internal Server Error

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

Please contact the server administrator, webmaster@sportsforpresident.com 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.

Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request."

Is there any way to recover all of the blog data? I don't recall doing anything that would have altered the site at all, but could someone let me know how I might be able to correct whatever mistakes were made?

Thanks so much!