Windows VM Extending VM Partition Greyed Out

Question

I allocated additional space on a Hyper-V host and when I log in to the VM and check the disk manager, I can see the unallocated space but I cannot extend my primary partition to it. I have read that the unallocated space has to be to the right of the partition being extended and that there cannot be other partitions in-between, but none of these apply to me. Anybody have any other ideas as to why the disk cannot be extended?

As a note: I have Hyper-V replica enabled which broke, it would not resume. I have since remove the replication but I cannot get the extend partition to work. I have done this many time and usually works like a charm, not sure what happened here.

Answer 1

Hi Falcon IT Services,

Please see if the volume can be extended with diskpart. Run diskpart in an elevated cmd window and use the extend [size=<n>] command to extend the partition.

https://learn.microsoft.com/en-us/windows-server/administration/windows-commands/extend

Best Regards,

Ian Xue

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Answer 2

Thank you again Ian, trying to extend it using diskpart returned the error that the disk is MBR and won't expand past 2TB. I hadn't thought about that, so the error save me a lot of head-scratching. Appreciate the help. Cheers.