Error getting the image size

[Yous]

Hello,

I was running ubuntu on Virtualbox for 4 months now. Today all of a sudden I am having issues opening the machine.

The error I am getting is as follows:

Could not open the medium
VDI: error getting the image size in (VERR_BAD_EXE_FORMAT)
VD:error VERR_VD_VDI_INVALID_HEADER opening image file (VERR_VD_VDI_INVALID_HEADER)

Could you please help fix this issue?

Thank you