We have a dll given to us by a third party. This dll was created using VSTO 2005 (ie. this dll includes the reference to the xls file, thisworkbook.cs, etc). We need to use this dll in our solution along with our in-house VS projects, but make this dll the Startup project. We don't need to debug this dll, but we need this external VSTO dll to the startup when I run/debug the other projects in the same VS 2005 solution. As far I know, VS only allows a project to be specified as Startup, but not an external dll. Please let me know how can I do this.


Re: Visual Studio Tools for Office How to make an external dll the Startup Project in the Solution


Hi Geetha,

Sorry for delaying reply

I am sorry to say that, as far as I know, your scenario could not be achieved. In Visual Studio 2005, when you press F5, the IDE do the following steps: recompile your code, and grant trust to the generated .dll file, and add the manifest to the .xls file. There is no way in Visual Studio to change these default steps. So every time you debug your project, the manifest of the file will be reset. Manifest is the only way you can customize which .dll will be loaded when the file is opened. If you just want to load the .dll given by third party, you can add a manifest to a .xls file which determines .dll to be loaded. But this is also not the debug model inside Visual Studio.