How to Add Custom Windows Templates on Virtualizor - Step by Step Guide

Last Updated: March 2026

Setting up Windows VMs manually every time? That's wasted hours.

A custom Windows template on Virtualizor KVM lets you deploy a ready-to-run Windows VPS in minutes — not hours. This guide shows you exactly how to do it. Step by step. No fluff.

What Is a Windows Template in Virtualizor?

A Windows template is a pre-built disk image. When you create a new VM, Virtualizor clones it instantly — no installation wizard, no manual clicking.

Think of it like a cookie-cutter. Build the shape once, use it forever.

Virtualizor supports KVM virtualization. KVM templates are stored as `.qcow2` or `.img` disk files on your server. Once registered in the panel, they appear as OS options when deploying any new VM.

Who Should Use This Guide?

This is for you if you are:

1. A VPS hosting provider running Virtualizor on KVM

2. A sysadmin managing multiple Windows servers

3. A reseller who needs fast, repeatable VM deployments

4. A DevOps engineer automating Windows VPS provisioning

Two Ways to Set Up Windows on Virtualizor KVM

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Before we start, know your options:

This guide covers all three methods.

Prerequisites

Make sure you have these ready:

1. Virtualizor 4.0+ installed and running

2. KVM-enabled server (Intel VT-x or AMD-V active in BIOS)

3. Official Windows ISO (Server 2019, 2022, or Windows 10/11)

4. SSH root access to the server

5. At least 50 GB of free disk space

6. Valid Windows license for production use

Part 1 — How to Upload a Windows ISO to Virtualizor

Step 1: Log in to the Admin Panel

Go to your Virtualizor admin panel: https://your-server-ip:4085

Log in with admin credentials.

Step 2: Go to the ISO Manager

From the left sidebar, navigate to:

Media → ISOs → Add ISO

Step 3: Add Your Windows ISO

Option A — Add via URL

Paste the direct download link. Virtualizor fetches it automatically.

Option B — Upload via SCP

Transfer the file directly to your server:

bash

scp windows_server_2022.iso root@your-server-ip:/var/virtualizor/iso/

Then register it in the panel by entering the file path.

Step 4: Confirm the ISO Is Listed

Go to Media → ISOs and verify it appears. If it's missing, fix permissions:

bash

chmod 644 /var/virtualizor/iso/windows_server_2022.iso

Part 2 — How to Create a Windows VM (Your Template Base)

Step 5: Create a New KVM Virtual Machine

Go to VMs → Add VM and configure it:

Click Add VM.

Step 6: Install Windows (Manual or Unattended)

Manual method: Connect via VNC from the Virtualizor panel. Follow the Windows setup wizard normally. 

Automated method (recommended): Use an `Autounattend.xml` file.

What Is Autounattend.xml?

It's a Microsoft XML configuration file. It answers every Windows setup prompt automatically — disk partitioning, language, admin password, everything.

You mount it as a second ISO alongside your Windows ISO. The installer reads it and runs without any user input.

A basic structure looks like this:

xml
<?xml version="1.0" encoding="utf-8"?>
<unattend xmlns="urn:schemas-microsoft-com:unattend">
  <settings pass="windowsPE">
    <component name="Microsoft-Windows-Setup">
      <DiskConfiguration>...</DiskConfiguration>
      <ImageInstall>...</ImageInstall>
    </component>
  </settings>
</unattend>

Pro Tip: Use the free Schneegans Unattend Generator to build a valid `Autounattend.xml` in under 5 minutes—no XML knowledge needed.

Can Windows Server be installed unattended on KVM? Yes — fully supported.

Step 7: Configure Windows After Installation

Once Windows is running, do these tasks inside the VM:

• Install VirtIO drivers — critical for KVM disk and network performance

• Enable RDP (Remote Desktop) for remote access

• Run Windows Updates fully

• Remove bloatware and unnecessary software

• Set a static admin password

These steps ensure your template is clean, optimized, and ready for production use.

Why VirtIO matters: Without VirtIO drivers, your Windows VM uses slow emulated hardware. With them, you get near-native performance on KVM. Always install before building the template.

Step 8: Shut Down the VM Completely

Never convert a running VM. Shut it down fully:

bash

virsh shutdown your-vm-name

Wait until the status shows `shut off` before moving on.

Part 3 — How to Build and Register the Custom Template

Step 9: Locate the VM Disk Image

Your KVM disk images are stored at:

/dev/vz/          ← if using LVM storage

/var/lib/vz/images/   ← if using file-based storage

Find your VM's disk:

bash

ls /dev/vz/ | grep your-vm-id

Step 10: Convert the Disk to qcow2 Format

Run this conversion command:

bash

qemu-img convert -f raw -O qcow2 /dev/vz/your-disk \

/var/virtualizor/templates/windows_server_2022.qcow2

The default Virtualizor template folder location is:

/var/virtualizor/templates/

This is where all your OS templates must live.

Step 11: Register the Template in Virtualizor

In the admin panel, go to:

Configuration → OS Templates → Add OS Template

Fill in the fields:

Click Save.

Step 12: Test the Template

Create a test VM using your new template. Verify:

• VM boots correctly

• RDP access works

• Network is functional

• Disk performance is normal (VirtIO active)

If everything checks out, your template is live and ready.

Troubleshooting Common Template Issues

Template Not Showing in Virtualizor?

Check three things:

1. File is in `/var/virtualizor/templates/`

2. Filename matches exactly what you entered in the panel

3. File permissions are correct:

bash

chmod 644 /var/virtualizor/templates/windows_server_2022.qcow2

Template Upload Failed?

Common causes and fixes:

Disk full — check with `df -h`, free up space

Wrong format — Virtualizor KVM needs `.qcow2` or `.img.`

Corrupted file — re-download the ISO or redo the conversion

Windows VM Running Slowly?

VirtIO drivers are almost certainly missing. Boot the VM, install VirtIO from the official Fedora VirtIO ISO, then rebuild the template.

Deployment Checklist

Use this before going live:

1. Windows ISO uploaded and registered

2. KVM VM created with correct specs

3. Windows installed (manual or unattended)

4. VirtIO drivers installed inside the VM

5. Windows fully updated

6. VM completely shut down

7. Disk converted to `.qcow2`

8. Template file in `/var/virtualizor/templates/`

9. Template registered in the admin panel

10. Test VM deployed and verified

Frequently Asked Questions

Q: How do I add an OS template to Virtualizor?

Go to Configuration → OS Templates → Add OS Template. Enter the filename, select KVM, and save.

Q: Where is the template folder in Virtualizor?

The default path is `/var/virtualizor/templates/` on your server.

Q: What ISO files does Virtualizor KVM support?

Standard `.iso` files. For Windows, use official Microsoft ISOs — Server 2019, Server 2022, Windows 10, or Windows 11.

Q: What is Autounattend.xml used for?

It fully automates the Windows installation. No manual clicks needed. Mount it as a secondary ISO, and Windows sets itself up using the file's instructions.

Q: Can I use Windows Server on Virtualizor KVM?

Yes. Windows Server 2019 and 2022 work fully on Virtualizor KVM. Ensure VirtIO drivers are installed in the template.

Q: What is KVM virtualization?

KVM (Kernel-based Virtual Machine) is an open-source hypervisor technology built into Linux. It runs isolated VMs — including Windows — with near-native performance.

Q: Why does my template keep failing to deploy?

Most common cause: the VM wasn't fully shut down before conversion. Always confirm `virsh shutdown` completes before running `qemu-img convert`.

Final Word

Custom Windows templates on Virtualizor KVM are not complex. The process is 12 steps. Do them in order. The payoff: you stop repeating the same 40-minute installation. Every Windows VPS deploys in under 5 minutes. Your clients get faster service. You save real hours every week.

Build the template once. Deploy it forever.

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