a http 500 means what it says an internal server error, (ie: the machine hosting the web site),
there is nothing you can do about it on the client machine,(ie: the machine your using iexplorer or what ever browser on)
it could be a simple error in the html of the default page/page your trying to view, or it could be a programming error in the backend , when the page tries to do something.
its the same as saying, My car is broken, can you tell me whats wrong with it?
could be many things,
sorry