# Other Windows device drivers
<a name="other-windows-device-drivers"></a>

The AWS VMClock device is a virtual clock device that is present on Nitro-based instances. The device appears in Device Manager under **System devices** as `AWS VMClock Device`. AWS provides a null (no-function) driver package for Windows that allows the operating system to recognize the device.

## Supported instances
<a name="aws-vmclock-supported-instances"></a>

The AWS VMClock device is available on Nitro-based instance types. For a list of Nitro-based instance types, see [Nitro-based instances](instance-types.md#instance-hypervisor-type).

## Supported operating systems
<a name="aws-vmclock-supported-os"></a>

The driver package supports the following versions of Windows Server:
+ Windows Server 2016
+ Windows Server 2019
+ Windows Server 2022
+ Windows Server 2025

## Driver installation
<a name="aws-vmclock-install"></a>

If the AWS VMClock device shows a warning icon in Device Manager, which indicates that no driver is installed, you can install the null driver package manually.

**To install the AWS VMClock driver**

1. [Download](https://s3.amazonaws.com/ec2-windows-drivers-downloads/AWSVMClock/Latest/AWSVMClock.zip) and extract the driver package from Amazon S3.

   ```
   Invoke-WebRequest https://s3.amazonaws.com/ec2-windows-drivers-downloads/AWSVMClock/Latest/AWSVMClock.zip -OutFile $env:USERPROFILE\AWSVMClock.zip
   Expand-Archive $env:USERPROFILE\AWSVMClock.zip -DestinationPath $env:USERPROFILE\AWSVMClock
   ```

1. Install the driver using `pnputil`.

   ```
   pnputil /add-driver $env:USERPROFILE\AWSVMClock\aws_vmclock.inf /install
   ```

1. Verify the device status in Device Manager. You don't need to reboot the instance.