Kaspersky Error 27300 Klif.sys-x64 May 2026

Microsoft’s Memory Integrity (part of Core Isolation) hypervisor-protects kernel mode drivers. If Kaspersky’s unsigned test driver conflicts, Windows blocks it with Error 27300.

The Fix:

Error 27300 (klif.sys-x64) is almost never a Kaspersky bug; it is a Windows security state conflict.

In 9 out of 10 cases, toggling Memory Integrity off and on again—or running a dedicated antivirus removal tool to erase legacy drivers—solves the problem instantly.

If you are still stuck, Kaspersky support has a specific GetSystemInfo utility that logs driver conflicts. Run that and share the sysinfo.txt file on the official support forum for a deep dive.

Have you encountered this error recently? Did the Memory Integrity toggle work for you? Let us know in the comments below.

Disclaimer: Always backup your system and data before modifying drivers or security settings.

How to Fix Kaspersky Error 27300 (klif.sys-x64) The Kaspersky Error 27300 typically occurs during the installation or upgrade of Kaspersky security products, such as Kaspersky Internet Security, Kaspersky Total Security, or Kaspersky Endpoint Security. This error indicates a failure to install a specific driver—most commonly klif.sys-x64 (Kaspersky Lightweight Inspection Framework)—which is critical for the software's real-time protection. Primary Causes of Error 27300 kaspersky error 27300 klif.sys-x64

Several factors can trigger this driver installation failure:

Leftover Files: Traces of previous Kaspersky installations or other third-party security software can conflict with new drivers.

System File Corruption: Corrupted Windows system files or damaged cryptographic services can prevent drivers from being signed or registered.

Third-Party Conflicts: Network drivers from applications like VMware, Cisco AnyConnect, or WinPcap often conflict with Kaspersky’s NDIS filter.

Windows Update Issues: Missing critical OS updates or pending restarts can disrupt the driver installation process. Step-by-Step Solutions 1. Use the Kaspersky Kavremover Tool

Before attempting a fresh install, ensure all traces of previous versions are gone.

Download the kavremover tool from the official Kaspersky website. Disclaimer: Always backup your system and data before

Run the utility, select the product you are trying to install/remove, and follow the prompts. Restart your computer immediately after the tool finishes. 2. Clean the Windows Cryptographic Folders

If the error is related to digital signatures (often accompanied by code 0x8000ffff), you may need to reset the Windows Update catalog:

Error 27300 when installing a Kaspersky application for home

Error 27300 a critical installation failure that occurs when the installer cannot correctly register or start essential system drivers

. This error typically stems from corrupted OS cryptographic services, leftover files from previous versions, or conflicts with third-party software. Kaspersky Support Forum Core Causes OS Integrity Violations : Issues with Cryptographic Services catalog database for driver signature validation often prevent the klif.sys-x64 driver from being added to the system. Leftover Drivers

: Residual files or registry entries from a previous Kaspersky installation can block new drivers from installing. Third-Party Conflicts : Drivers from applications like VMware Workstation Cisco AnyConnect

use similar NDIS filter mechanisms and may conflict during the installation process. Unsupported Hardware : This error is common on systems using ARM (Snapdragon) If you previously had other antivirus software, their

processors, which are not supported by standard Kaspersky versions. Step-by-Step Resolution 1. Clean Residual Files

Standard uninstallation often leaves behind fragments that cause driver errors.

Error 27300 when installing a Kaspersky application for home 20 Mar 2025 —

If you previously had other antivirus software, their own filter drivers remain active and conflict with klif.sys. Use the Autoruns tool from Microsoft Sysinternals.

Steps:

Warning: Disabling Windows Defender drivers may require temporarily turning off “Memory Integrity” (Core Isolation) in Windows Security.

Follow these steps in order to resolve the installation failure.

Once you have resolved the error, follow these best practices: