I need help with the .NET 6 image depreciation

Hello Tony,

Thank you for reaching out Q/A.

Your 13 standalone VMs are not immediately impacted, and you likely don't need to take emergency action right now.

When an Azure Marketplace image is deprecated, its availability for new deployments changes — but your existing VMs continue running normally. Deprecation removes the image from the Azure Marketplace catalog but does not remove the OS disks of your existing VMs.

Reference: https://learn.microsoft.com/en-us/azure/virtual-machines/deprecated-images

All existing VM operations continue to work normally, including start, stop, restart, deallocate, backup, and restore. Your current workloads are not affected, and the VMs will keep running.

The one thing that gets blocked:

After the enforcement stage, you will not be able to create new VMs or reimage existing VMs using the deprecated image, since Azure no longer allows provisioning from that image version

https://learn.microsoft.com/en-us/azure/virtual-machines/deprecated-images#key-points

The legacy Windows Server 2022 images that pre-installed .NET 6 will begin deprecation after June 9, 2026. The deprecation will enter the enforcement stage at the end of 2026.

Reference: https://techcommunity.microsoft.com/blog/azurecompute/incoming-changes-for-window-server-2022-marketplace-image-users/4262423

For standalone VMs already in production, you can keep them running. The breaking impact is primarily on VM Scale Sets, since scale-out operations require creating new instances from the deprecated image. Since you confirmed you have no VMSSs, this high-severity impact doesn't apply to you.

Recommendations:

1. Check if your apps actually use .NET 6. If they don't, the image deprecation has minimal practical impact on your running VMs.
2. If your apps do depend on .NET 6, plan to migrate them to .NET 8 or .NET 10, as .NET 6 is officially end-of-life and no longer receives security patches outside these marketplace images.
3. Before end of 2026, consider migrating to the new Windows Server 2022 image (without .NET 6 pre-installed) when you next provision or redeploy VMs — not urgently, but as part of your normal maintenance cycle.

Since you’ve got 13 existing VMs, you don’t need to rush into anything today unless you plan to reimage or spin up new servers from that image.

That said, here’s a simple and practical path forward:

Identify your VM images • Run Azure CLI or PowerShell to confirm the exact imageOffer / SKU / version used by each VM. For example:

az vm show \
  --resource-group MyRG \
  --name MyVM \
  --query "storageProfile.imageReference.{publisher:publisher,offer:offer,sku:sku,version:version}" \
  --output table

This helps you clearly identify whether any of your VMs are based on the deprecated image.

Choose a replacement image by reviewing the Windows Server 2022 listings in the Azure Marketplace. Select a SKU that does not include .NET 6, or use the “latest” option to ensure you receive continuously updated and supported builds.

For migration planning, if you are not reimaging existing VMs or creating new VMs from the deprecated image, you can continue running your current environment without any immediate changes until a planned maintenance window.

When you are ready to proceed, it is recommended to first deploy a test VM using the new image. This helps validate application compatibility and ensures there are no runtime issues before moving production workloads.

After successful validation, you can proceed with a controlled migration or redeployment of your production VMs during an approved maintenance window.

Hope this helps! Please let me know if you have any queries.

Hello Tony Bligh,

Greetings! Thanks for raising this question in Q&A forum.

Welcome to Azure! Your instinct is right for your existing 13 VMs, you most likely don't need to do anything right away. Let me explain this in simple terms so it's clear exactly what the .NET 6 image deprecation notice means for you and what, if anything, you need to act on.

What does "image deprecation" actually mean?

Think of a VM image like a template used to create a VM. Once your VM is created and running, it no longer depends on that original template it runs from its own copy of the disk. So deprecating the image does NOT affect your running VMs in any way. They will continue to start, stop, restart, and run completely normally.

What IS affected after the deprecation date:

Two things get blocked after the enforcement date creating brand new VMs from the deprecated .NET 6 image, and performing a "reimage" operation (which rebuilds a VM from scratch using the original image). Since you have no VMSSs (Virtual Machine Scale Sets), which use reimage heavily, this further reduces your exposure.

Step 1: Do a Quick Check on Each VM

The most important thing to verify is whether any of your 13 VMs use an image that has a purchase plan (this applies mainly to third-party Marketplace images). Run this Azure CLI command for each VM to check:

az vm show --resource-group <your-resource-group> --name <your-vm-name> --query plan

If the result comes back as null or empty which it will for most standard Microsoft images you have nothing to worry about and no action is needed.

If it returns values like name, publisher, and product, that means the image has a purchase plan and you should plan to migrate those VMs to a newer supported image before the enforcement date.

Step 2: Note the Enforcement Date from the Notice

Check the deprecation notice email or Azure Service Health alert for the exact enforcement date. You don't need to act before that date for your existing VMs, but it's good to mark it on your calendar.

Step 3: Plan for Future Deployments Only

Going forward, if you ever need to create new VMs, simply choose a newer supported image (such as a .NET 8 or .NET 9 based image, or a standard Windows/Linux image depending on your needs) instead of the deprecated .NET 6 one. Your existing 13 VMs are not affected by this restriction.

Step 4: Keep an Eye on Azure Advisor

Go to Azure Portal → Azure Advisor and check the Operational Excellence tab. Azure Advisor will flag any of your VMs that may need attention due to image deprecation, so you have a clear dashboard view without needing to manually check each one.

In short your 13 existing VMs are safe and will keep running normally. The deprecation only matters when creating new VMs or doing reimages, and since you're not doing either of those right now, you can relax!

If this answer helps you kindly accept the answer which will help others who have similar questions.

Best Regards,

Jerald Felix.