# Windows 11 on Proxmox VE: q35, OVMF, vTPM, VirtIO and snapshots

> Build a Windows 11 26H2 VM on PVE 9.2.2 with UEFI, vTPM 2.0, VirtIO drivers, QEMU Guest Agent and a snapshot chain that can be rebuilt.

**Tested on**

- Build: 26300.9457
- Edition: Pro (26H2)
- Architecture: x64
- Evidence: E2
- Verified: 2026-10-28
- Test machine: PVE 9.2.2 VM 361; q35/OVMF/vTPM 2.0/Secure Boot; 8GB/4 vCPU; SATA system disk + VirtIO NIC/vioser; Windows 11 Pro 26300.9457

VM 361: Windows 11 Pro 26H2, UEFI, Secure Boot On. QEMU/Standard PC strings are expected in a VM; the evidence is the edition/build and firmware state. Click to open full size.

## The short answer

A Windows 11 VM on PVE is not “create VM, next, next”. The supported configuration is:

- **q35** machine;
- **OVMF (UEFI)** firmware;
- **EFI disk** + **vTPM 2.0**;
- **Secure Boot** if you want the Windows 11 baseline;
- **VirtIO** disk/network with the driver ISO available;
- **QEMU Guest Agent** installed;
- a **snapshot** after the clean state.

Our VM 361 uses a SATA system disk because Windows Setup could not see the VirtIO SCSI disk before drivers. That is a VM workaround, not a physical-hardware recommendation.

## VM settings that matter

| Setting | Lab value | Why |
|---|---|---|
| Machine | q35 | Modern PCIe/PCI layout |
| BIOS | OVMF (UEFI) | Windows 11 requirement |
| EFI disk | Enabled | UEFI variables |
| TPM | vTPM 2.0 | Windows 11 requirement |
| Secure Boot | On | Supported baseline |
| CPU | `host` | Nested virtualization/performance |
| RAM | 8GB | Practical for Windows 11 + browser |
| Disk | 256GB, SATA (lab) | Setup visibility before VirtIO |
| Network | VirtIO | Performance; needs driver |
| Display | Standard/SPICE | Console access |
| Agent | QEMU Guest Agent | Shutdown/IP reporting |

## Build order

1. Upload the official Windows 11 ISO and the VirtIO driver ISO to PVE storage.
2. Create the VM with q35/OVMF, EFI disk, vTPM, 8GB RAM, 4 vCPU, `host` CPU.
3. Add a disk and a VirtIO network device. Add the VirtIO ISO as a second CD-ROM.
4. Boot the Windows ISO, install Windows, and load the VirtIO storage driver if the disk is invisible.
5. Install the VirtIO network/serial/balloon drivers from the driver ISO.
6. Install QEMU Guest Agent, then verify from the host.
7. Install Windows updates and the vendor tools you need.
8. Shut down cleanly and take a snapshot named for the state.

## Verify the guest

```powershell
winver
Get-PnpDevice -Status Error
Get-Service QEMU-GA
```

On the PVE host:

```bash
qm agent 361 ping
qm guest cmd 361 get-osinfo
```

If the agent does not respond, check the VirtIO serial device and the guest service. A VM can run without the agent, but snapshots/shutdown/IP reporting are less graceful.

## qm config sanity check

From the PVE host, confirm the VM is what you think it is:

```bash
qm config 361 | egrep '^(machine|bios|efidisk0|tpmstate0|scsi0|sata0|net0|agent):'
```

Expected shape for this lab: `machine: q35`, `bios: ovmf`, an `efidisk0`, a `tpmstate0`, a disk, `net0` on VirtIO and `agent: 1`. If `bios` is SeaBIOS or there is no TPM, Windows 11 may install but not in the supported configuration.

## Troubleshooting matrix

| Symptom | Check | Fix |
|---|---|---|
| Setup cannot see the disk | Disk bus + VirtIO ISO | Load the VirtIO storage driver, or use SATA for the lab |
| No network after install | VirtIO NIC driver | Install from the VirtIO ISO, then reboot |
| Agent not running | `Get-Service QEMU-GA` | Install the agent, enable the VirtIO serial device |
| Very slow console | Display/SPICE settings | Use SPICE or RDP; do not judge performance from the console |
| Snapshot grows forever | Snapshot chain | Consolidate/delete old snapshots; keep a separate backup |

## Snapshots

Use snapshots for **lab state**, not as your only backup:

- `win26h2-pre-wsl` — clean install
- `win26h2-wsl2-devdrive` — WSL/Dev Drive
- `win26h2-hvci-off` / `win26h2-hvci-on` — HVCI experiment

Snapshots live on the PVE storage and can grow; keep a separate backup of anything you cannot rebuild. Do not snapshot a running VM with an active database and call it consistent.

> **Caution: VirtIO ISO version**
>
> The lab used `virtio-win-0.1.302.iso` while the PVE wiki recommended a different current version at the time. Driver conclusions are tied to the ISO actually used; record it.

## What this page does not do

- No GPU passthrough (see the separate page).
- No activation guidance.
- No claim that a VM score equals bare metal.

## Host sizing and nested virtualisation

- [Proxmox host memory: what Windows guests really cost](https://winbook.fyi/en/hardware/homelab/host-memory/) — measured on a 31.2GB host running two 8GB guests.
- [A mini PC as a Proxmox host](https://winbook.fyi/en/hardware/homelab/mini-pc-host/) — cores, RAM, NIC and storage sizing.
- [Virtualisation flags](https://winbook.fyi/en/hardware/cpu/virtualization-flags/) — why `--cpu host` is needed for WSL2 inside the guest.

## Sources

- [Proxmox VE — Windows 11 guest best practices](https://pve.proxmox.com/wiki/Windows_11_guest_best_practices)
- [Proxmox VE — Windows VirtIO drivers](https://pve.proxmox.com/wiki/Windows_VirtIO_Drivers)
- [Proxmox VE — QEMU Guest Agent](https://pve.proxmox.com/wiki/Qemu-guest-agent)

---

Source: https://winbook.fyi/en/windows/dev/pve-windows-vm/