VirtualBox fails to load Tails 1.4~rc1

When following Tails website documentation about Tails within VirtualBox, it fails at the following step when using Tails 1.4~rc1 (verified):

“Click on the CD icon on the right of the window and select Choose a virtual CD/DVD disk file… to browse for the ISO image you want to start Tails from.”

I get the following error message:

Failed to open the optical disk file /home/amnesia/tails-i386-1.4-rc1.iso.

Could not get the storage format of the medium
‘/home/amnesia/tails-i386-1.4-rc1.iso’
(VERR_NOT_SUPPORTED)

Details

Result Code: VBOX_E_IPRT-ERROR (0x80BB0005)

Related issues

Is duplicate of #8891 (closed)

Original created by @mercedes508 on 9348 (Redmine)

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