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I've been using VirtualBox for weeks for school. Tonight, out of the blue, my virtual guest locks up and when I reset, there are so many issues.

I first had an issue with my screen no longer resizing as I drag the window - so I thought I would just resinstall Guest Additions. I ran the software manually (by opening the image and clicking "Run Software") and it appears to have done whatever it needed to. But the problem persists.

Now when I try to mount the Guest Additions image, I get the following error:

Unable to mount VBOXADDITIONS_4.3.6_91406 Error mounting /dev/sr0 at /media/user/VBOXADDITIONS_4.3.6_914061: Command-line mount-t "iso9660" -o [...] exited with non-zero exit status 32: mount: unkown filesystem type 'iso9660'

Can someone please help me out? I'm a little desperate here... since I have projects due for class and can't really do anything efficiently now.

Worth Noting: I performed the same steps on a backup image I had of my VM, and the same issue is occurring. I have no idea what's changed...

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provide the full path for your GuestAdditions.iso file. –  Avinash Raj Feb 26 '14 at 5:11
Sorry about that; updated. –  ctote Feb 26 '14 at 5:13

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