I can't get the code written in Visual Studio to work.

The excel workbook opens but the code does not seem to run at all.

I have installed Visual Studio .NET 2003, Microsoft Office 2003, and
Visual Studio Tools for Microsoft Office System (in that order) with
all the required options (.NET programmability support in Office). I
create a new Visual C# Project in Visual Studio, using the Excel
Workbook Template of the Visual Studio Tools, I write some code in the
ThisWorkbook_Open() function, but the code doesn't seem to run.

Any idea why this happens?

Thanks in advance
GC.