> Source: [sk165772](https://support.checkpoint.com/results/sk/sk165772)

# sk165772 - Endpoint Security VPN client fails to connect to the Remote Access Gateway, with "Failed To Load Virtual Network Adapter" error message

| Property | Value |
|----------|-------|
| Solution ID | sk165772 |
| Date Created | 2020-08-24 |
| Last Modified | 2021-02-18 |
| Technical Level | Advanced |
| Products | Security Gateway, Endpoint Security |
| Versions | R82.10, R82, R81.20, Cloud, E89.X, E88.X |
| OS | Windows |

## Symptoms

- * Endpoint Security VPN client fails to connect to the Remote Access Gateway, with "Failed To Load Virtual Network Adapter" error message. Connection is stuck at 47%.
* Issue only occurs after Endpoint Security VPN client is upgraded.
* When the user runs `ipconfig /all` in the Windows command line, the Check Point Virtual Network Adapter is not present in the interface list.
* The `setupapi.dev` logs in Windows lists the following errors for the VNA adapter:  
  dvi: {DIF_INSTALLINTERFACES}   
  !!! dvi: Loading module 'C:\\WINDOWS\\system32\\vnaap_coinstall.dll' failed.  
  !!! dvi: Error 193: %1 is not a valid Win32 application.  
  !!! dvi: Error 193 loading CoInstaller(vnaap_coinstall.dll, _vna_co_installer@16)  
  !!! dvi: Error 193: %1 is not a valid Win32 application.  
  dvi: Default installer: Enter 21:43:36.707  
  dvi: Default installer: Exit  
  dvi: {DIF_INSTALLINTERFACES - exit(0x00000000)}
* User may also experience VPN connection is stuck at 82% and fails without error messages and trac/log shows the following error:  
  \[ 52368 51052\]\[18 Feb 17:47:31\]\[vna\] vna_cfgmgr_if_change_notification: 54-65-b5-af-7e-0b  
  \[ 52368 51052\]\[18 Feb 17:47:31\]\[om\] om_utils_iterate_interface_list: called  
  \[ 52368 51052\]\[18 Feb 17:47:31\]\[\] cpii_get_interface_list_ex: allocating 73c8 size buffer for cpii_get_interface_list  
  \[ 52368 51052\]\[18 Feb 17:47:31\]\[\] doing list verifications do_again == 10  
  \[ 52368 51052\]\[18 Feb 17:47:31\]\[\] list_len == 3  
  \[ 52368 51052\]\[18 Feb 17:47:31\]\[vna\] vna_cfgmgr_if_change_notification: not ready

## Cause

**Environment:** Symantec Endpoint is installed and SecureBoot is enabled on the laptop.  

Issue is related to an old Symantec driver that is preventing the VNA adapter from loading on bootup, as it is not signed with Microsoft. The driver in question is Teefer.sys that is not updated to the latest version.   

Teefer.sys (in version 14) does not allow the VNA adapter to load after the Endpoint Security client upgrade. Once Symantec is uninstalled and upgraded with the Teefer.sys drive 14.2 (that is signed with Microsoft), VNA adapter is seen and VPN connections are once again working.  

Refer to: <https://knowledge.broadcom.com/external/article?legacyId=tech250045>

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## Solution

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