Web to case using c#

Hello Everyone,

I am trying to create a case from a custom form built for our website.

I tried to pass on all the details which are mandatory to create a case.

1. Do I need to send the owner id as well to create a case?
2. I could not find any syntax / reference on how to send the owner id

Below is the code that I am using to create a case.

Currently I am getting "An unexpected error occurred." and not getting any other details.

On the other hand I am able to update and delete case without any issues.

I am quite new to dynamics crm and tried to check existing posts to see if there is a similar case. Please point me to right direction. 

Thanks very much.

Kind Regards,

Sudhakar