Shared Folder not working in Mint 19

[Pez4040]

I had some shared folders defined on my VB Linux Mint 18.3 system. They were working fine. I just upgraded to Mint 19 and I am not able to see any files in the directories. I can see that I am in the vboxsf group. I've logged off of my id and then logged back on. I've restarted my system but still not able to see the files. I've looked around many different pages and tried various things but nothing is working. All of this seems to be setup properly but I am missing something.

jeff@jeff-VirtualBox /media $ id jeff
uid=1000(jeff) gid=1000(jeff) groups=1000(jeff),4(adm),24(cdrom),27(sudo),30(dip),46(plugdev),113(lpadmin),130(sambashare),999(vboxsf)
jeff@jeff-VirtualBox /media $ pwd
/media
jeff@jeff-VirtualBox /media $ ll
total 20
drwxr-xr-x     5   root   root    4096 Jun 13 08:33 ./
drwxr-xr-x    23   root   root    4096 Jul 10 10:26 ../
drwxr-x---+    3   root   root    4096 Jul 10 15:43 jeff/
drwxrwx---     2   root   vboxsf  4096 Jun 13 08:33 sf_Docs/
drwxrwx---     2   root   vboxsf  4096 Jun 12 20:46 sf_Pics/
jeff@jeff-VirtualBox /media $ tail -3 /etc/group
sambashare130:jeff
vboxsf999:jeff

Any help would be much appreciated.

[socratis]

Did you upgrade the Guest Additions (GAs)? We're going to need to see a VM log from a complete VM run:

• Start the VM from cold-boot (not from a paused or saved state) / Observe error / Shutdown the VM (force close it if you have to).
• With the VM completely shut down (not paused or saved), right-click on the VM in the VirtualBox Manager and select "Show Log".
• Save only the first "VBox.log", ZIP it and attach it to your response. See the "Upload attachment" tab below the reply form.

[PeterE]

Did you find a solution for your problem?

[socratis]

@PeterE,
Apparently 'Pez4040' found the solution, that's why most probably there was no reply/followup. Just follow the instructions on ch. 4.2.2. Guest Additions for Linux of the User Manual...

[PeterE]

I have the VBoxGuestAdditions.iso in the virtual DVD drive, but it is probably not mounted, because the directory /opt is empty. What can I do now?

[AJGringo619]

It won't be mounted under /opt. Check /media/your_username/VBox_GAs_5.2.18.

[PeterE]

In /media I can only find a directory sf_D_DRIVE
When I try to eject it I get this error message: Could not unmount the currently mounted media/drive (VERR_PDM_MEDIA_LOCKED).
I can force it to eject and then insert it again.

[AJGringo619]

(Sorry for the late reply; I thought I would be notified automatically on a response.)

So...did the ISO mount?