Based on my research, the .vmgs file is used for version 8.2 or higher Hyper-V virtual machines and is used to store the virtual machine guest state.
All the .vmgs files are fixed size 4,194,816 bytes and contain some JSON information.
We don’t know why this file is missing. We can try to manually copy this file and rename it to see if the problem can be solved.
Or
We will see VMCX, VMRS, and VMGS binary files in the Snapshots folder after create a Checkpoint.
https://adamtheautomator.com/export-vm/
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