I want to install OMV on a SandDisk 64GB Ultra for my raspberry pi 4 / 4GB.
So I used the OMV_Odroid_XU4_HC1_HC2.img.xz and "installed" it via double click on my memory card.
I also tried out Etcher but it did the same thing.
After I start my pi i get this screen:
Its formatted FAT32.