Shared folder is empty from Mac(host) to Win10(guest)

[superk]

Description:
I created a shared folder with the GUI(that is, Devices->Share Folders). Then I browsed the path "\\VBOXSVR" in the guest OS, but found it was empty.
I was absolutely sure that:
1. path of the folder being shared was correct
2. guest additions was correctly installed(in fact, shared clipboard worked all the time)
Even more mysteriously, the shared folder happened to work for a short while yesterday for some unknown reason till I rebooted the guest OS. Too late to regret

Profile:
MacOS(host OS): High Sierra 10.13.3
Windows(guest OS): 10.0.10240
VirtualBox: 6.0.4 r128413 (Qt5.6.3)
Guest Additions: 6.0.4

[socratis]

Shutdown the guest. Start the guest. Usually that fixes it.

On top of that, there have been several issues with VirtualBox Shared Folders in the 6.0.x series. See the "Known Issues" in the "Discuss the 6.0.0 release" post.

[superk]

Restarting doesn't work. In fact, I have just upgraded from 5.2.X to 6.0.4 in hope that the new release will fix this issue.
In other words, this issue exists for 5.2.X too with other conditions the same.

[socratis]

Downgrade to 5.2.26. Do the same for your Guest Additions, i.e. re-install them after you downgrade to 5.2.26. Then we need to see a complete VBox.log, from a complete VM run, where the problem occurs:

• Start the VM from cold-boot (not from a paused or saved state) / Observe problem / 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.

[superk]

Downgrading neither work. Log attached.
Thanks!

[socratis]

1. path of the folder being shared was correct

Yes, the folder is shared correctly:

00:00:03.182771 SharedFolders host service: Adding host mapping
00:00:03.182781     Host path '/Users/superk/Desktop/shared', map name 'shared',
                    writable, automount=false, create_symlinks=false, missing=false

Can you try to change the Auto-mount option to True?

2. guest additions was correctly installed(in fact, shared clipboard worked all the time)

Yes on that too:

VirtualBox VM 5.2.26 r128414 darwin.amd64 (Jan 25 2019 19:57:40) release log
00:00:11.004192 VMMDev: Guest Additions information report: Version 5.2.26 r128414 '5.2.26'

If the Auto-mount option doesn't work, I wouldn't know where to look at next...

[superk]

Unfortunately, no miracle
Log attached as well.
Could you please tell me where to report this issue so that the contributors will notice it?
VirtualBox was awesome for me but for this issue. It's really inconvenient not being able to share files between host and guest.
Nevertheless, much appreciated for your help!

[socratis]

Again, nothing out of the ordinary...

Can you take the following steps and see if there's a difference?

• Remove the shared folder. Boot the VM, login, shut it down from within the guest.
• Create a new share, on a different location. By default OSX includes a "/Users/Shared" folder. Share that one.
• Boot the VM, see what happens...

Could you please tell me where to report this issue so that the contributors will notice it?

When we figure out that it's indeed a real issue, and not something wrong with your specific setup, I'll be the first to point you to the tracker. But since this hasn't been reproduced by anyone else, I'm a little bit hesitant to have you open yet another [Invalid] or a [WorksForMe] ticket...

Speaking of your setup, can you think of anything out of the ordinary that you've installed in your system? Can you post the output of the following?

• 
  kextstat | grep -v com.apple
  ls -ald /Applications/*
  ls -ald /Applications/Utilities/*

[superk]

Sorry for late feedback. I almost gave up

Can you take the following steps and see if there's a difference?
Remove the shared folder. Boot the VM, login, shut it down from within the guest.
Create a new share, on a different location. By default OSX includes a "/Users/Shared" folder. Share that one.
Boot the VM, see what happens...

Non, everything is the same.

Speaking of your setup, can you think of anything out of the ordinary that you've installed in your system?

Nothing special. Configuration of the host as attached.

BTW, I have found a way to bypass this issue:
1. Create an additional network adapter on the guest and attach it to the "host-only adapter";
2. Install samba on the host and configure it only available to the vboxnet0 interface;
3. Access the shared directory on the guest through samba. it works!
In my thought, this solution can do the job, meanwhile the shared directory on the host keeps invisible and inaccessible physically(almost?) from other computers on the same intranet with the host.

[socratis]

drwxr-xr-x@  3 superk  admin  102 11 29 17:11 /Applications/Docker.app

I don't like this. At all actually! Docker installs a parallel installation of VirtualBox (who knows what version) and guess the main thing that it affects due to its configuration? Networking!

I don't know what's going on or what could be going on, and neither do I plan to investigate it any further, sorry...