PIIX3 cannot attach drive to the Secondary Master

[o1sowise]

I just cloned a VM and now I get this error when I try to start them both simultaneously:

Failed to open a session for the virtual machine XP Sandbox.

PIIX3 cannot attach drive to the Secondary Master (VERR_SHARING_VIOLATION).

Result Code: NS_ERROR_FAILURE (0x80004005)
Component: Console
Interface: IConsole {db7ab4ca-2a3f-4183-9243-c1208da92392}

fyi - the error come when the 2nd VM starts, regardless if it's the original or the clone.

[o1sowise]

Nevermind.
It was the CD drive. It could not be attached to both VMs.
Based on this finding, I'd like to keep it off of both VMs and dynamically add it to the one I need, when I need it.
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