McNoob

Hi. Thanks for the welcome. I've tried resetting the NVRAM using a Windows USB keyboard (Winkey+Alt+P+R). I've tried holding it in first and then starting up, starting up and holding as soon as the chime sounds and waiting until after the chime. I get the same behavior. Before installing the Boot Manager, I could use the key combinations, but now I just have a black screen after startup. Is there any other advice you can give?

Hi. I am running a late 2014 Mac Mini A1347 running the latest compatible OS. I installed the app, enabled the boot manager and rebooted. The Mac Mini now shows nothing after the chime. There is no boot manager, and the OS doesn't load, no matter how long I let it run. I am also unable to boot into the recovery screen. Any help would be appreciated.