Failed to open the hard disk /home/ajana/Downloads/mer-sdk-nemo-i486-vm-sda.vdi.

Could not get the storage format of the medium '/home/ajana/Downloads/mer-sdk-nemo-i486-vm-sda.vdi' (VERR_NOT_SUPPORTED).

Result Code: VBOX_E_IPRT_ERROR (0x80BB0005)
Component: Medium
Interface: IMedium {53f9cc0c-e0fd-40a5-a404-a7a5272082cd}
Callee: IVirtualBox {c28be65f-1a8f-43b4-81f1-eb60cb516e66}