Using .NET 3.5 is it possible to deploy an Office add-in to the program files directory that installs for all users and for the users to not receive an untrusted publisher warning?
Deploying your VSTO add-ins to all users states the following:
If you are developing your solution with Visual Studio 2010 and targeting .NET 4, an alternative to signing with a Trusted Publisher certificate is to install the add-in into the machine Program Files location. This location also needs administrative privilege to write to and will be inherently trusted by VSTO, so there will be no trust prompt even if the solution is not signed with a Trusted Publisher certificate.
If I understand this correctly installing to the program files directory with an add-in that targets .NET 4 would not require signing with a trusted publishers certificate.
Currently targeting .NET 4 is not an option. If I add a custom action to my installer that grants FullTrust permission to code executing in my deployment target directory do I still have to sign my manifest with a trusted publisher certificate?
If using .NET 4 is not an option, then I think creating inclusion list should be what you are after. You might want to take a look at these articles:
How to: Add or Remove Inclusion List Entries
Trusting Office Solutions by Using Inclusion Lists