Revit Add-in Loading List

[Chuck.Ross]

I've been writing some Add-ins for Revit.

When starting Revit I am prompted whether to Always Load, Load Once, or Do Not Load Add-ins.

I am also using the Add-in manager tool to help with debugging. At some point, I loaded an add-in from my development directory. Now, every time I open Revit it prompts me whether to load the add-in from that location - (Which I want for it to never do.) 

Is there a way to clear out, or remove an entry from the list of add-ins that Revit prompts to load on each start-up?

Thanks for any help in the matter,

Chuck

[moturi.magati.george · Accepted solution]

Hi @Chuck.Ross 

Revit generally loads addins from the following folders:

In a non-user-specific location in "application data":

• C:\ProgramData\Autodesk\Revit\Addins\Revit 2025\

In a user-specific location in "application data":

• C:\Users<user>\AppData\Roaming\Autodesk\Revit\Addins\Revit 2025\

If you are seeing an addin loading from a development folder, it means you have a manifest file which is at the above locations but references the Dll's in your development folder

[Chuck.Ross]

Hi @moturi.magati.george 

Thank you for the reply, unfortunately, neither of those file locations contain the .addin manifest, nor the .dll files Revit is trying to load. Rather it is trying to load the app from a repos file on my C: drive where I save my Visual Studio Projects.

[jeremy_tammik]

I remembered there is a third location, but not where it is. I asked the Gemini chatbot:

Jeremy: a Revit add-in is loaded by revit when an add-in manifest file s detected in a certain location. i believe there are three such folders. two are listed in the developer guide:

• In a non-user-specific location in "application data": C:\ProgramData\Autodesk\Revit\Addins\Revit 2018\
• In a user-specific location in "application data": C:\Users<user>\AppData\Roaming\Autodesk\Revit\Addins\Revit 2018\

It replied:

You're absolutely right! Those are two of the primary locations where Revit looks for add-in manifest files.

Here's the third location:

• In a user-specific location in "local application data":
  • C:\Users\<user>\AppData\Local\Autodesk\Revit\Addins\Revit 2018\

Key Points:

• Manifest File: The crucial element is the manifest file (usually an XML file with a .addin extension). This file provides essential information about the add-in, such as its name, version, assembly location, and more.
• Load Behavior:
  • Revit typically loads add-ins from these locations during startup.
  • The order of loading might vary depending on the location and the add-in's configuration within the manifest.
• User-Specific vs. Application-Wide:
  • User-Specific (Roaming and Local): Add-ins placed here will only be available for the current user.
  • Application-Wide (ProgramData): Add-ins located in this folder will be available to all users on the machine.

I hope this helps! Let me know if you have any other questions about Revit add-ins.

[Chuck.Ross]

@jeremy_tammik ,

Thank you for this response. Again, unfortunately, no luck there either... I on working on Revit 2022. My folder structure in this location looks like this: C:\Users\<user>\AppData\Local\Autodesk\Revit\Autodesk Revit 2022.

In that folder, there are folders CefCache, CollaborationCache, Journals, and DDGraph file. no Addins or any .addin or .dll files I'm working on...

Still stumped on this one... 

[Chuck.Ross]

@moturi.magati.george , @jeremy_tammik ,

Ohmygosh.... I found the problem .addin file in the C:\ProgramData\Autodesk\Revit\Addins\2022 folder.... Somehow I had a manifest file simply named ExternalTool.addin that pointed to the .dll in the development folder... not sure how it got there, but it was indeed the culprit.

Thank you again for your time spent helping me, I truly appreciate it!

[jeremy_tammik]

Maybe the application manager created it. I assume so.