Deploying to Device From Windows - BP Only - Error

I have an existing project that used to deploy to device from windows.

After upgrading to 4.1.5, I get an error:
LogPlayLevel: UnrealBuildTool: Picking the default remote server
LogPlayLevel: UnrealBuildTool: Remote compiling requires a server name. Use the editor (Project Settings, IOS) to set up your remote compilation settings.
LogPlayLevel: UnrealBuildTool: Doing xcode-select --print-path
LogPlayLevel: UnrealBuildTool: ERROR: Failed to start local process for action (“Cannot start process because a file name has not been provided.”): -o BatchMode=yes ${CURRENT_USER}@ “cd “/” && xcode-select --print-path”
LogPlayLevel: CommandUtils.Run: Run: Took 0.763725s to run UnrealBuildTool.exe, ExitCode=5

This is a BP-Only project, no plugins.

I built a new empty rpoject, and it deploys fine.

There are no c++ files inproject - what else could cause build system to think it needs to compile?

Thanks For Your Help

In your project settings, under packaging make sure you have blueprint nativization method set to disabled.

Let me know if that helps

rOb