convert an Excel 2010 addin to a 2007 addin (both VSTO)

Question

I am currently working on an Excel 2010 add-in which formerly was an Excel 2007 add-in. Somewhere in the process of switching computers, the add-in was converted i think.

Answer 1

Typically, when I am developing against multiple versions of Office with VSTO Add-ins, I have a project for each version of Office I am targeting. I put all common code between the projects into a single project (typically the oldest project) and use linked files, I add the common files to the newer projects. This allows me to write one set of common core code, abstracted from the requirements of each version of Office. This means I am no longer fighting the different ways VSTO is compiled for each version of Office. This can be made easier with shared folders and virtual machines, so I can develop and test without multiple computers. It is by no means graceful, but it works well for me. This should allow you to develop your VSTO Add-in against both Office 2007 and Office 2010 without much issue.