.NET security in VB web service

Question

I'm having trouble accessing an object in VB (.NET) code for a Web Service on a hosted machine. My local version of the code runs fine, but when I deploy the web service to the hosted environment, I'm seeing strange results. The problem seems to revolve around a 3rd party DLL that I'm using. This DLL has been defined in the web service as a reference, with the corresponding Interopt.DLL being generated by Vis Studio. The DLL is registered on the hosted platform via REGSVR32, as it is locally. But when I instantiate an instance of a class from DLL in the hosted environment, I cannot seem to set any properties in the instance of the object.... It's almost acting as if it were somehow "read-only" ...? Does this make any sense? I'm wondering if there's not some aspect of .NEY security at play here, but am not sure where to look first. If this does involve security, should there security exceptions showing up in some .NET log someplace? Thanks for any idea, Jim