Hello
Thank you for your question and reaching out.
- Kindly verify if the parent disk of avhdx is the remaining vhdx by "inspect disk" in Hyper-V console. avhdx file could be generated by either checkpoint in hyper-V console or backup tools .
2.Once confirmed, kindly try to remove the vm1 from roles in Failover cluster manager, then proceed with manual merge steps.
- Also please try to Export this VM and Import to different Hyper-V Host and see if its working correct disk size and data.
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