A. This question refers to situations such as if you have a guest running on VMware ESX and you perform a virtual to virtual (V2V) migration to Hyper-V. ESX has its own virtual additions, which install drivers and services into the guest OS. When you migrate to Hyper-V, Hyper-V adds its own integration services, assuming the OS doesn't already have the integration services built in.

It wouldn't be ideal to leave the additions from the old hypervisor in the guest, and so as part of the V2V migration the old additions should be removed as soon as possible. Removing them will help you avoid complications.

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