I manage several virtual machines via VirtualBox, and one of the first things I do is share a folder between host and guest OS, but when I ran the command this time, I got an error:

/sbin/mount.vboxsf: mounting failed with the error: Protocol error

Turns out, I forgot to share a folder via the VirtualBox UI, but that possibility didn’t even occur to me until much later.

So, as short as this blog post is, I’m sure someone else using VirtualBox will run into this, and before you dive into all kinds of solutions, double check that first. :)

Featured image by James Wheeler.

Comments (1)

Previously posted in WordPress and transferred to Ghost.

Juliano
March 17, 2015 at 11:31 pm

I lost near an hour trying all other complex solutions that didn’t work. Then after I read your post I realized I have renamed one existent shared folder when I copied the OVA from a colleague. I then renamed it back to the original and everything works fine. Thanks!