In NinjaTrader’s Control Center, select New > NinjaScript Editor.
Open any indicator by double-clicking it in the explorer on the right.
Press F5 to compile.
Look at the error list at the bottom. The NinjaScript File column identifies the file; the other columns show the error description and line number.
Double-click an error to open the file at the problem location.
NinjaTrader compiles all installed NinjaScript files, so you can open any indicator to run this check.