What version of checkra1n are you using, and GUI or CLI? GUI Mac OS - 9.8.1 & 10
What is your host system (OS version? Hackintosh? VM? etc.)? Mac OS
How are you connecting to the device (USB-A? USB-C? Apple/3rd party cable? Through a USB hub?)? USB-C
What are the steps to reproduce the issue?
Open it on the mac catalina
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What do you expect, and what is happening instead?
I expect the app to open, it doesn't start, quits with error code 255
Mar 28 12:39:11 FVFXW583JK78 com.apple.xpc.launchd[1] (com.apple.xpc.launchd.oneshot.0x1000000c.checkra1n[1382]): Service exited with abnormal code: 255
Does the issue also occur if you enable Safe Mode?
Tell us about your setup:
What are the steps to reproduce the issue?
...
What do you expect, and what is happening instead? I expect the app to open, it doesn't start, quits with error code 255
Mar 28 12:39:11 FVFXW583JK78 com.apple.xpc.launchd[1] (com.apple.xpc.launchd.oneshot.0x1000000c.checkra1n[1382]): Service exited with abnormal code: 255
Does the issue also occur if you enable Safe Mode?
Any other info, error logs, screenshots, ...? https://pastebin.com/7S3QAFDJ