I'm trying to boot Linux Mint 19.3 (based on Ubuntu 18.04) from a raw EFI USB flash drive on a Windows 10 host using VirtualBox 5.2.12.
I have successfully created the .vmdk stub, and the VirtualBox VM when run as administrator sees the stub and loads Grub off the USB. It is an encrypted Linux partition, and the kernel loads and boots and I get asked for the password and the encrypted partition is successfully decrypted. It is at this point that I get a "VirtualBox - Error" dialog with this message "The I/O cache encountered an error while updating data in medium "ahci-0-0" (rc=VERR_ACCESS_DENIED). Make sure there is enough free space on the disk and that the disk is working properly. Operation can be resumed afterwards."
Normally VERR_ACCESS_DENIED is associated with VirtualBox not being run as administrator, but this is not the case. I am running as administrator.
I realize I am running an oldish version of VirtualBox. I am wondering if anyone knows with any certainty if the issue could be the version I'm using. I would rather not go through upgrading unless I know it will solve the problem.