> For the complete documentation index, see [llms.txt](https://docs.thousandeyes.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.thousandeyes.com/product-documentation/global-vantage-points/endpoint-agents/installing/windows/npcap-upgrade.md).

# NPCAP Driver Upgrade Management

The Endpoint Agent Client leverages the NPCAP library to support running certain [network tests](/product-documentation/global-vantage-points/endpoint-agents/installing/windows/endpoint-agent-installation-reference.md#extended-network-tests-support-for-windows) and gather device metrics on Windows devices. The default NPCAP library distributed with the installer is version **1.86**.

### Verify the installed Npcap version on Windows

To confirm the Npcap OEM build present on a Windows endpoint, inspect the **DisplayVersion** value under the Npcap uninstall registry key (64-bit Windows example):

```
reg query HKLM\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Uninstall\NpcapInst
```

The reported version should align with the Npcap build bundled with your Endpoint Agent release; see [Endpoint Agent release notes](https://docs.thousandeyes.com/release-notes/2025) if you need the exact bundle for a specific client version.

Our software undergoes testing against the versions of NPCAP that we distribute. By default, your account group only permits the use of these versions. However, if you are running other software that uses this library, you may have a version of NPCAP installed that is either older or newer than the version we provide. If you'd like to use a different version, just follow these [instructions](https://docs.thousandeyes.com/product-documentation/global-vantage-points/endpoint-agents/managing/manage-endpoint-agent-settings#advanced-agent-settings) to include it. Please note that you must use a minimum version of 1.0 to use our software.

If you enable another version, please know that our QA process does not test against these other versions. You must test and report any issues to us promptly.

## Report an Upgrade Issue

Please open a [support case](https://docs.thousandeyes.com/product-documentation/getting-started/getting-support-from-thousandeyes) if you experience issues with the upgrade. In some scenarios, ThousandEyes may disable auto-updates temporarily on your production Account Group until the issue gets resolved.

Auto updates are important for stability, security, and product function.