Hi,

I have written an RTD server (.dll) in C# which works beautifully in
one instance of excel.

However, if I open a separate instance of excel I cannot use the RTD
formulae, I get NA#. My understanding, according to this article

http://support.microsoft.com/kb/284883

was that a new instance of the Server will be created for each
instance of excel when using a dll - so each excel has it's own
callback. This is clearly not the case. Can anyone help?

Many thanks

Rob