Thanks for taking the time to reply Don. I don't think the problem is anything to do with the actual code of the server DLL, I'm not actually using the example code, I'm selecting data from an Oracle database using a connection string which has the user name and password of the database included. This all works fine when tested from my PC. The problem you mention with 'rights' is a possiblity but I must admit I don't really know where to look. I've set the virtual IIS directory on my PC to have 'anonymous access'.