I have followed the following guide to try and create an MSI to deploy a VSTO add in for Outlook. https://msdn.microsoft.com/en-us/library/cc442767.aspx?f=255&MSPPError=-2147217396
I have carefully followed this guide on two occasions, ensuring in particular that I placed the registry keys in every place I can imagine they would be need to be in order to be detected.
The MSI is created successfully and installs successfully also, the problem is that when I run Outlook after the MSI is installed, Outlook does not recognize the Add In and load it.
If I use Click once to install the add in it is recognized by outlook without any issue. The problem with that is that we want to install the application silently using SCCM and clickonce cannot be deployed silently.
What could possibly be going wrong?
The issue in this case, was that the guides code for installing the prerequisite "Visual Studio 2010 Tools for Office Runtime" did not work properly and the prerequisite was not installed.
Any user that needs to run the add in will need the VSTO tools from this link installed
Hopefully this will be of some help to anyone else
EDIT: For anyone in the UK - The registry entry "LoadBehavior" must be spelled exactly as it appears here. I used the UK spelling "LoadBehaviour" and it was the sole reason my install was not successful. I was held back for several days due to this.