The Pi4 is not supported by RetroPie yet - either with the image(s) provided on the download page or through the manual installation (over Raspbian).

From: https://blog.petrockblock.com/powerblock-raspberry-pi-power-switch/

@mitu I'll work on it tomorrow after work. Thanks a bunch for your input mitu. Means a lot to me. I'll let you know how it turns out. Thanks a bunch.

@Nextus Make sure you've purchased the NESPi Case +, the latest revision from RetroFlag. There were issues reported with the previous case and the higher power requirements of the Pi 3+. @angry_bucket I don't think that's correct, but curious to know more about your experience. RetoFlag's safe shut-down script advises to set this to On before installing the scripts. I followed this and everything works fine (as long as EmulationStation is running). https://github.com/RetroFlag/retroflag-picase [Edit] I purchased one of these a month ago - love it.

@mitu So I tried this but couldn't boot into safe mode... no terminal available. Will have to rebuild the image. Thanks for the help, good for future reference.

@djawadi Looks like a bad written image or undersized sd card. Please give more details - https://retropie.org.uk/forum/topic/3/read-this-first

@jbryan1984 Wobbly pop (beer) money ! haha

@rbaker maybe he means 2Volts... then feck it. He's lucky to even see the CLI. Sort your PSU out, mate!