Comment # 7 on bug 1184392 from Stefan Hundhammer

From the most recent VBox.log:

00:00:00.379691 Log opened 2021-04-06T13:22:25.630074000Z
...
00:00:00.944516 Changing the VM state from 'CREATING' to 'CREATED'
00:00:00.949102 SharedFolders host service: Adding host mapping
00:00:00.949110     Host path '/work/src', map name 'work_src', writable,
automount=false, create_symlinks=true, missing=false
00:00:00.949256 SharedFolders host service: Adding host mapping
00:00:00.949262     Host path '/work/tmp', map name 'work_tmp', writable,
automount=false, create_symlinks=true, missing=false
00:00:00.949408 Changing the VM state from 'CREATED' to 'POWERING_ON'
...
00:04:15.179691 VMMDev: Guest Log: vboxsf: Host rejected mount of 'work/src'
with error -2