ContributionsMost RecentMost LikesSolutionsRe: NullPointer on ReadyAPI startup - Macbook 10.13.3 OS Actually, the error is because your primary monitor is not selected to be your default. You do not have to unplug your monitors, just go into your System Preferences > Display >Arrangement and make sure the monitor with the little white bar is on your laptop screen. If not, then I think you just drag it to the correct one. Unfortunately, you cannot have an external monitor be your "primary", but at least you can still have other monitors. Still something seems broken IMO, but this is a better work-around. Re: NullPointer on ReadyAPI startup - Macbook 10.13.3 OS I had the same issue and it turns out it was because my laptop was plugged into a docking station with 2 additional monitors. I don't know if it is my MacBook pro, macOS, ReadyAPI software or my docking station. Anyway, when I unplug from the dock and launch ReadyAPI it comes up just fine. Frustrating! Wasted a few hours trying to figure this out. That will be part of my troubleshooting steps from now on.