Following are the various file types registered on a user’s machine when Windows Virtual PC is installed: .VMC (Virtual Machine Configuration), .VHD (Virtual Hard Disk), .VUD (Virtual Undo Disk), .VSV (Virtual machine Save state), .VFD (Virtual Floppy Disk), .VMCX (vmc eXtended), . vpcbackup. To backup a VM: 1. Shutdown VM. This’s important since save state files (.VSV) are not compatible across machines. Save state stores VM system state and is processor dependent. Moving it to another machine may not boot VM 2. If VM has undo disk enabled, commit or discard the changes. If you want to keep undo disk for future use, you need to backup .vud file also. VUD file is created at same path as of .VHD file. 3. At this time, also backup .VHD and its parent disk (you can find parent disk by using settings of VM). Backup .VUD file if undo disk’s still present. 4. Backup .VMC file. 5. A diff disk .vhd keeps pointer of parent disk as absolute and relative path. So when you backup make sure relative path is in same order.
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