> Source: [sk168156](https://support.checkpoint.com/results/sk/sk168156)

# sk168156 - Error related to cpepmon.sys during the installation of EPS.MSI

| Property | Value |
|----------|-------|
| Solution ID | sk168156 |
| Date Created | 2020-07-25 |
| Last Modified | 2020-12-31 |
| Technical Level | Advanced |
| Products | Endpoint Security |
| Versions | Cloud, E89.X, E88.X |
| OS | Windows |

## Symptoms

- * When trying to install the Endpoint Security Client, it fails on cpepmon.sys and roll back the installation.
* Installation the Virtual Network Adapter (VNA) driver fails, and following SK159192 does not resolve the issue. The displayed error is: Unable to open '\\\\.\\vna_ap': The system cannot find the file specified

## Cause

A third party software - Device Lock (<https://www.devicelock.com/>) is causing a conflict.

## Solution

This solution requires authentication. Please log in to view the full solution.

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