Need help running B1WS

Hello,

I've downloaded the B1WS and follow all the configuration instruction. But after running the ASPNET_Sample and try to login to my SAP B1, i got this error

"Client found response content type of 'text/html', but expected 'text/xml'. The request failed with the error message: -- "

"Server Application Error

The server has encountered an error while loading an application during the processing of your request. Please refer to the event log for more detail information. Please contact the server administrator for assistance. --.!"

I have check the DIServer log file, but its not helpful. Anybody can give me the idea of what went wrong??