Warning: One or more disk image files are not currently accessible

I have set up Ubuntu 14.04 LTS on VirtualBox.

Everything seems to work ok so far, but every time I launch VirtualBox I get this pop-up with a warning message.

I believe this warning started to appear when I changed the number of processor cores of the VM in Settings.

Is this a big issue and if so how can I fix this ?

This is what I see when I click the check button

Solution 1:

I had the same issue and was confused until I looked more closely and realized it was looking for the iso I originally placed on my desktop, which I had since thrown in the trash. It appears your message is telling you the same thing.

After successfully installing the ubuntu VM(/Users/user/VirturalBox VMs on mac), I discarded the ISO, but the drive is still mounted, causing the error, or warning.

I was able to select the iso listed in the dialog and press remove, and upon restart of VirtualBox, the issue was resolved.