RevitAPI.dll and RevitAPIUI.dll are required references for the interaction between the Macro Manager and the Revit macro IDE. If they are inadvertently removed from a module, use this procedure to restore them.
- Select the module in the Macro Manager.
- Click Edit.
- In the Project Explorer of IDE, right-click on the references section, and select Add Reference.
- In the Add Reference dialog, click the Browse tab.
- Navigate to \Revit <release>\Program.
- Select RevitAPI.dll and RevitAPIUI.dll.
- Click OK.
The references are restored and the macro will build, debug, and run as needed.