Why are shared folders missing?

Question

virtual box

I installed VirtualBox Guest Additions by going mount cdromto a folder mediaand running the file .run
. The program set up a shared folder at the point /home/shared/, everything worked out and shared files appeared there after the reboot ...
Then I started setting up nginx, probably did some reboots, I go into /home/shared- and it's empty there ...
And lsmod | grep vboxoutputs nothing.
I did everything again, I noticed that after the reboot there were mediano files. And the shared folder is still empty.
When I ran it again .run, it was written in the logs that the previous version was being deleted ...
It turns out that guest addons are installed, but do not work .. Maybe you need to put some process into autoload? Tell.

Answer 1

The group changed from vboxsf to root (it’s not clear when and how), the rights changed, changing back didn’t help, just demolished the folder and reappeared as it should.

Answer 2

When creating a folder, forgot to check the box "persistent" and auto mount?