Cannot delete snapshot due to hidden differencing image

[simon marshall]

Fairly regularly, I find that when I try to delete a snapshot, the VBM (VBox Manager) reports that it cannot because there is more than one child hard disk. However, the VBM does not show any indication of its existence in the snapshot hierarchy. I can only see the extra disk in the VMM (VMedia Manager), where I can delete it and then successfully delete the snapshot from the VBM.

However, that the VBM and VMM disagree about the disk/differencing hierarchy must be a bug, right?

In all of the situations where this has occurred, I have done nothing more complex than periodically create snapshots and periodically delete them. The disks are not shared across machines and I've not cloned any machines. Unfortunately, it's not reproducible, it just occasionally happens. I've come across this problem on 2 different hosts with 4.1.4. I think I've seen it in earlier versions too.

[simon marshall]

virtual machine

[simon marshall]

last log

[simon marshall]

VBM when I attempt to delete snapshot 4.1.2

[simon marshall]

Error when I attempt to delete snapshot 4.1.2

[simon marshall]

VMM when I attempt to delete snapshot 4.1.2

[simon marshall]

This, or something extremely similar, has hit me again, this time in 4.1.6. I have snapshots that look like this:

build
  baseline
    work
      Current State

I select "baseline" and hit "Restore Snapshot". After a short time, VB reports the VM as inaccessible in the VB manager. However, if I close and restart the VB manager, VB is happy with the VM and shows that it has almost completed the restore to:

build
  baseline
    work
    Current State

as you can see in attachment "intended snapshots".

However, if I look at the media manager, the (I think) diff image for the original current state remains, though it is shown as not attached, as you can see in attachment "resulting diffs".

Please can someone change the Version to 4.1.6?