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Virtualbox file share permission problem

Virtualbox (by Oracle) is my favourite virtualizer and was the first thing I installed on my new Mac, so that I can run Fedora Linux on it.  A Mac is great for common users and I would advise anyone to buy a Mac instead of that other sad legacy system that always gets riddled with viruses and malware.

However, I am an engineer and need to be able to test and debug things and write low level programs - I am always rooting around in the weeds and need Linux for that.

So I wanted to share my Mac Documents directory.  After some sleuthing I found that it gets mounted as /media/sf_Documents, but I then got a permission problem when I tried to access it.

The solution is to add yourself to the vboxsf group and then reboot the virtual machine:
$ su -
password
# usermod -a -G vboxsf herman

Just logging out and loggin in again is not sufficient.

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