Connection to remote COM object works in Windows Forms application but not in ASP.NET application

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Jos? Ram?n Rodr?guez - 30 Dec 2003 19:59 GMT

Hello there,

The following code causes "Specified cast is not valid" exception when line
3
executes inside an ASP.NET application. I have tried this with several
components. Exactly the same code works if
connecting locally (i.e with localhost) and it always works from a Windows
Forms application even if connecting to another computer.

Here is the code:

Type type = Type.GetTypeFromProgID("CorporaServer.CorporaAppServer",
"RemoteServer");
Object objTest = Activator.CreateInstance(type);
CorporaAppServer CorporaServerObj = (CorporaAppServer)objTest; // exception
"Specified cast is not valid" raised here

Anybody knows why this could happen? Thanks in advance,

Jose R. Rodr?guez

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enrico sabbadin @ infinito - 05 Jan 2004 01:11 GMT

looks like tehre are some issues with type library registration / interop
assembly ..
In windows forms it works likely because there is no marshaling taking
place.

> Hello there,
>
[quoted text clipped - 16 lines]
>
> Jose R. Rodr?guez

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Jos? Ram?n Rodr?guez - 05 Jan 2004 13:17 GMT

Hello Enrico, thanks for answering. My Windows forms application is a .NET
application also so I figure it would be doing the same marshalling that is
done when using COM objects from an ASP.NET application, it's all .NET
right?

I later tested with a Web application in my little network at home and it
worked well, I figure it must be just some configuration problem either in
the COM+ application or in the ASP.NET application. My network at home has
no domain controller and the settings of the COM+ application were
different, I'll try this this morning at work.

Thanks again for answering,

Jose R.

> looks like tehre are some issues with type library registration / interop
> assembly ..
[quoted text clipped - 23 lines]
> >
> > Jose R. Rodr?guez

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enrico sabbadin @ infinito - 06 Jan 2004 00:49 GMT

inline

> Hello Enrico, thanks for answering. My Windows forms application is a .NET
> application also so I figure it would be doing the same marshalling that is
> done when using COM objects from an ASP.NET application, it's all .NET
> right?

nope .. the windows form .NET thread is an STA thread so there is no
marshaling when calling the STA com component (i guesses it's an sta)

> I later tested with a Web application in my little network at home and it
> worked well, I figure it must be just some configuration problem either in
[quoted text clipped - 3 lines]
>
> Thanks again for answering,

I suggest you to test the caller and callee thread id to know when
marshaling is taking place or not

> Jose R.
>
[quoted text clipped - 26 lines]
> > >
> > > Jose R. Rodr?guez

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Connection to remote COM object works in Windows Forms application but not in ASP.NET application

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