Missing menus in CP

[Chrismk]

Running 3.8.7 Patch Level 2
Logged into the CP this morning and the left frame has the following message in it:
------------------
Internal Server Error

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

Please contact the server administrator, webmaster@***.co.uk 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.
-----------------

The main right frame displays.
New users are also now being asked for a referrer and there is nothing in the captcha window.

What's happened and how do I resolve it?
Thanks.

[Lynne]

And did you do as the error says and check the server error log? I would contact your host about this error if you haven't changed anything and see if they have changed something.

[Chrismk]

Thanks for the reply.
I didn't understand the logs so contacted the hosts.
Evidently something called suhosin had been installed?

[Lynne]

Suhosin will cause the type of errors you are seeing if it is not configured correctly. Did you tell the host what errors you are getting so they can configure it correctly for you?

[Chrismk]

It's a shared environment.
I've never heard of the program!
The hosting company have resolved the problem.
Thanks.

Chris