ragman11

I tested it again with USB 3.0 cables, 3 different nvme Adapter, all are working and booting on PI4 USB 3.0 port. Raspian is booting up fine from USB3 ports...

 With an USB3 Cable it does not boot, USB 2 cable runs fine

> I have no problem with booting from usb3. Ugreen usb3.2 case with kingston a400 ssd. are you using a usb 3.2 cable? blue inside usb connector. With a usb2.0...

> I use the cable that comes with the case. It is a 3.2 cable. ok, still strange, I‘m using a Intenso 250GB M.2 SSD PCIe Premium, 2100 MB/s, (PCI...