[Revit 2027] Changes to All-Users Add-in Installation Paths and Deployment Considerations

When creating an installer to distribute add-ins in a bundle format that supports multiple versions, such as Revit 2025 through 2027, I encountered a phenomenon where "the add-in just won't load in Revit 2027 for some reason!"

The cause was a change in the specification for the location of All-Users add-ins introduced in Revit 2027. I am sharing this information briefly to help others avoid falling into the same trap.

Overview of the change: From ProgramData to Program Files

In Revit 2027, for improved security, the location from which All-Users add-ins are loaded has been changed from ProgramData to Program Files.
Therefore, even if you place the add-in for 2027 in the ProgramData folder as you did for versions up to 2026, Revit 2027 will not look there.

📁 Comparison of specific paths

Version	Installation directory for All-Users add-ins
Up to 2026 (Old)	C:\ProgramData\Autodesk\Revit\Addins\20XX C:\ProgramData\Autodesk\ApplicationPlugins
2027 onwards (New)	C:\Program Files\Autodesk\Revit\Addins\20XX C:\Program Files\Autodesk\ApplicationPlugins

*Note: The installation location for Per-user add-ins (under %APPDATA%, etc.) remains supported as before.

Points to note and countermeasures when creating an installer

When creating an installer that consolidates past versions and 2027 onwards (using WiX, Inno Setup, InstallShield, etc.), you need to dynamically switch the installation target (deployment destination) based on the target Revit version.

• Add-ins for 2026 and earlier 👉 Place in C:\ProgramData...
• Add-ins for 2027 and later 👉 Place in C:\Program Files...

If you have settings that indiscriminately dump everything into either ProgramData or Program Files, one version or the other will definitely fail to load the add-in, so please do not forget to configure folder control for each version.

Impact on the API side

With the change in the installation location, the value returned by the Revit API's Application.AllUsersAddinsLocation property has also been changed to the new Program Files path starting from 2027.
If your code processes paths using this property, please be aware that the behavior will change.

I hope this information is helpful for your add-in support and installer revisions for Revit 2027!