NS_ERROR_FAILURE after plug-out of an USB drive which contained an ISO which was attached to the DVD drive of the VM

[pall]

I recently installed Windows 7 into a VM. Therefore I mounted an Win7-ISO from an USB drive to the DVD drive of the VM. Everything worked perfect until I plugged out the USB drive since I didn't need it anymore. Now I get the following error:

Hard disk '/home/*/.VirtualBox/HardDisks/Windows 7.vdi' with UUID {30991e32-9cc9-4cfa-a765-eb2cddfbc702} cannot be directly attached to the virtual machine 'Windows 7' ('/home/*/.VirtualBox/Machines/Windows 7/Windows 7.xml') because it has 1 differencing child hard disks. Result Code: NS_ERROR_FAILURE (0x80004005) Component: Machine Interface: IMachine {6d9212cb-a5c0-48b7-bbc1-3fa2ba2ee6d2}

I think that this is a result of the plug-out of the USB drive, because now the machine can't find the iso which is attached to the DVD drive anymore.

I guess this is a bug, right? There should be a possibility to deactivate attached isos when the machine is turned off.

[aeichner]

Please reopen if still relevant with a recent VirtualBox release.