I searched various forums and found no answer. Maybe some of you had such a problem.
I purchased the X96 max plus. I installed CoreELEC on the SD card. The CoreELEC system starts up without a problem. After inserting the HDD into USB, the system does not see the disk in any slot. The HDD is in your pocket and has its own power supply. I have 2 flash drives which are visible. I took out the SD card, fired up the android system, turned on Kodi, the HDD via USB is visible and everything works.
Is there a setting in CoreELEC to make the HDD visible?