Unable to attach an unassigned disk to new VM

@Smit Shah I hope you are doing well, please Ensure the Disk is in the Correct Resource Group & Region

• The disk must be in the same region and same resource group as the VM you are trying to attach it to.

Check VM Compatibility:

• Ensure the VM size supports the disk type. For example:
  • Premium SSD requires a Premium Storage-compatible VM (e.g., DS-series, GS-series).
  • Standard HDD/SSD works with most VM sizes.
• If the VM doesn’t support the disk type, you may need to change the VM size or create a new VM with a compatible size.

Check Permissions: Ensure you have the necessary permissions (e.g., Contributor role) to view and attach disks in the subscription and resource group.

Some useful links

• https://learn.microsoft.com/en-us/azure/virtual-machines/attach-os-disk?tabs=portal
• https://learn.microsoft.com/en-us/azure/virtual-machines/windows/attach-managed-disk-portal

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Hi Smit Shah
continuing with Jose Benjamin Solis Nolasco adding additional information
Ensure the disk is unattached you can, check under Virtual Machines > Settings > Disks in the suspected VM’s settings to see if the disk appears in the Data disks list.

If it is still attached, go to the VM’s Disks section, select the disk, and click Detach. Wait for the process to complete before attaching it to a new VM
Also, check compatibility and refer to this documentation on Azure managed disk types for more information
And refer the below SS based on the role we can make the changes and attach the disk

Please refer the below documentation Frequently asked question they mentioned about DIsk related query
Frequently asked questions about Azure IaaS VM disks and managed and unmanaged premium disks

And also refer the below links on this query conversation about managed disk it might helps you to resolve your issue
https://stackoverflow.com/questions/50707153/azure-managed-disk-not-showing-when-trying-to-attach-to-vm

Please let me if you have any other query or need anything other information

If this information helpful, could you please click an upvote👍

Thanks Akshay

The issue is not with the process of attaching disks however the disk itself is not showing up on the list when I try to go attach it.

Jose, the disk and VM are both in East US and under the same resource group.

But I am thinking that might be the issue.

My VM is D2s_v3 with LRS Standard SSD

I can change the storage type to anything but would prefer standard HDD if supported since its mostly older data on that drive.

How do I find the list of compatible SKUs?

Hi Smit Shah,
Based on your latest comment, what I understand is that when you're trying to create a new VM and attach unassigned disk to it, the disk does not appear as an option. Similarly, for an existing VM, the disk is also not shown when trying to attach it. However, for unassigned disks, they do appear in the portal during attachment — is that correct? if that is the case

If your VM is existing in Zone 1 and the managed disk is in Zone 2, the disk won’t be available to attach when setting up the VM. Azure requires that both the VM and the disk be in the same zone for them to be compatible.

Below is the screenshot showing that the VM and disk were created in the same Zone 1.

Please let me know if you have any further query ping me in comment

@Akshay kumar Mandha

This is what my VM looks like

Was B4MS, tried D4sV3 as well.

This is how the current disk is configured.

Both are in the same resource group and subscription.

However, it does not show up on the list.

What am I doing wrong here?