External Tool Failure (Revit Add-in) Revit Cannot Run the External Application "Land F/X", System.IO.FileLoadException (Using One of Our Revit Plugins)



You received one of the following error messages after installing the Land F/X Revit 3D Connection plugin and opening Revit:

External tool failure

Revit cannot run the external application "Land F/X". Contact the provider for assistance. Information they provided to Revit about their identity: Land F/X, www.landfx.com


Could not load file or assembly




Could not load file or assembly LandFXRevitAddin.dll, or one of dependencies. Operation is not supported. Exception from HRESULT 0x80131515.





You've encountered a default Revit error message, which is an indication that we still need to either fix or assign a specific error message to the issue you're experiencing. (This can happen as we work on the beta version.)





1. Drop down the Show Details option in the error message, and take a screenshot of the result. This section will likely contain key information for us to replicate and fix this error message.




2. Send us a technical support ticket that includes

  • Your screenshot of the expanded error message
  • Your file

  • Your Land F/X project data
  • A step-by-step description of what you were trying to do when you encountered the error


We’ll use all this information to replicate the error so we can fix it.

Last modified on Oct 17, 2019


  • Land F/X

Our software tailors AutoCAD to the needs of landscape architects, irrigation designers, and other professionals. We automate your most tedious tasks and ensure accuracy, giving you more time to design.

Log in to landfx.com: