Many thanks for your help,

So should I be doing the following when updating my vfp com object:

1)make changes to the com object: including adding and delteing methods, changing the order of the methods, signatures, etc.
2)rebuild the vfp COM object
3)recompile the asp.net application
4)re-distribute the asp.net application and the vfp com object to the web server once again

And... then am I good to go. Or... do I have to request a new indentifier each time I rebuild my com object from within vfp and then recompile the asp.net application. If so, do I have to re-register the vfp com object on the web server and redo com+ ?

Regards,
Neil


>Hi,
>
>you're violating one of the basic rules of COM interface design.
>That is once an interface is published, it should not change.
>
>We'll have to dig into lower level COM to understand why that is important.
>
>When you compile a COM object in VFP, each method and property you expose from it is given a unique identifier (a plain integer value).
>
>COM Automation objects can be early bound & late bound. What does that mean?
>In the early binding scenario the compiler of the lanuguage you're using the COM object from, resolves the unique identifier of your methods/properties at compile time. When using late binding the Compiler emits code to resolve this unique identifier at runtime.
>
>see methods "Invoke" & "GetIDsOfNames" of the IDispatch interface for more details.
>
>Now what propably happens is that when you change the order of the methods
>in your COM object, some methods are assigned different unique identifiers.
>
>And since ASP.Net early binds to your COM object, the code breaks.
>
>Normally you should be able to resolve this by recompiling the parts of your ASP.Net application that use your COM object.
>
>Regards
>Christian