Try running the engine directly from its folder as administrator.
I.e . right click \UE_4.18\Engine\Binaries\Win64\UE4Editor-Cmd.exe and select Run as administrator. Then load the project from the engine’s project browser that opens.
You can also go to the exe file properties > Compatibility and check the Run this program as administrator. Then you can launch the project in every way you’d like.
That did the trick for me.