-26612 Http:// Status code 500

i, 

I am testing a web application and my load generator and window resource monitor services are in server 2008 ..

When I was started , I got thiis error.

..26612: HTTP Status-Code=500 (Internal Server Error)...

will explain you all test step.

Firstly, the application is based ajax and I tested it with truclient..

When I have tested , I encountered some problems.I didn't arrange init,action,end blocks..Then I used only action option..

Then it is ok..

Secondly I converted truclient script to webhtmlhttp and I used it on controler..

Then I had a lot of error that is http://status code 500.. I had only this error.

Thirdly I used just truclient script on controler.I had no error..

Please help me, I have to test it with webhttphtml script.