"Failed to save settings" for registered VM if HostNetwork or NATnetwork is not available in new host => Fixed in SVN

[Socratis]

Problem

• Create a VM, no need for HD, CD or anything like that. See the "TestDOS.vbox" that's attached.
• Select the NATnetwork option, with a NATnetwork that exists on Host A, for example "VBoxNATnetwork", that I have only created on Host A.
• Disable the adapter.

• Take that .vbox file to another host, Host B, where the "VBoxNATnetwork" does not exist.
• Register the VM, run the VM. No problems.
• Open the settings. Press OK to close the settings.

Error message:

Failed to save the VM settings.

Empty of null NAT network name is not valid.

Result Code: E_FAIL (0x80004005)
Component: NetworkAdapterWrap
Interface: INetworkAdapter {e925c2aa-4fe4-aaf6-91c5-e9b8ea4151ee}

Followed by:

The machine settings were changed while you were editing them. You currently have unsaved setting changes.

Would you like to reload the changed settings or to keep your own changes?

Workaround

Enable the network adapter in question, change the "Attached to" option to something else, preferably "Not attached". Disable the network adapter again, if you want to.

Solution

Force the non-enabled adapters to become "Not attached".

[Socratis]

Try to change the settings of this VM, as long as you don't have a NATnetwork named "VBoxNATNetwork"

[Socratis]

And the related discussion in the forums that reminded/forced me to actually open the ticket: ​https://forums.virtualbox.org/viewtopic.php?f=7&t=88014

[gombara]

Fixed in the development branch by r72482.

[janitor]

Jumped the gun here... Sorry.