Unable to install Ubunbtu on Windows Virtual Box

[ManuChadha]

I have downloaded ubuntu-20.04-desktop-amd64 file and am trying to install Ubuntu on Virtual Box. I always get error

"
The Installer encountered an error copying files to the hard disk [Errno 5] input/output error
"

I am not even using a disk! Why am I getting this error and how can I solve the problem? I also tried installing 18.04 from an iso but it just hangs with a black screen right at the start.

[scottgus1]

Start the guest from full normal shutdown, not save-state. Run until you see the problem happen, then shut down the guest from within the guest OS if possible. If not possible, close the Virtualbox window for the guest with the Power Off option set.

Right-click the guest in the main Virtualbox window's guest list, choose Show Log. Save the far left tab's log, zip it, and post the zip file, using the forum's Upload Attachment tab.