Recently I needed to create an installer for my add-ins using Inno Setup installer. Inno Setup is a free ware professional installer. It lets you use Pascal) to create special code to help you install the add ins.
Luckily, over at Dutch Gemini’s website he has helped with plenty of the code to get there. Very well done, I might add.
It looks like he uses a single add-in file for Excel 2003 and below and Excel 2007 and above (for ribbon purposes). I prefer to have all my code in a single XLA file (if I’m not using Excel DNA) for the main code and then a separate XLAM file for the ribbon. So I had to change some of his code to account for that.
I basically changed his functions CopyTheAddIn and HookAddinToExcel to account for the XLAM file when it is Excel 2007 and above. The functions UnhookAddinFromExcel and RemoveTheAddIn also need to be changed to uninstall the add-ins and delete all the add-in files.