Hi,
I'm trying to migrate from El Captain systems with coexisting Windows 10. All problems started when I put M2 disk with Windows 10. It has dominated EFI boot, so to boot in MacOS I had to put pendrive with Mojave install to be able to choose anything on boot that works (Clover).
I have erased partitions on my old Mojave SSD and tried to install Catalina. Olarila Mojave or Olarila Catalina - created both pendrives, both gives me the same - black screen after some lines of log.
Do I need to remove M2 disk to install MacOS? I donot remember the order I did with previous disks.