NetExtender breaks connection to Microsoft services

Introduction

A problem earlier this year has been identified with SonicWall NetExtender interfering with Microsoft 365 authentication. This issue was raised by SonicWall with the ID SMA-4585.

The VPN client, NetExtender, alters the following registry key: HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Connections
This modification results in a failure of authentication and cryptic error messages across all Microsoft 365 applications.

Resolution

This issue has been fixed with the release 10.2.338 of the SonicWall NetExtender on January 2024. Thus, you have to update your Clients.

Workaround

1. If you still need older versions of SonicWall NetExtender in your environment, then you have to apply the following workaround:
   Run the CMD as an Administrator
2. Run the following command: RunDll32.exe InetCpl.cpl,ResetIEtoDefaults
3. Select in the newly opened window “delete personal…” and run it.
4. Download the SARA agent.
5. Run the following commands in the place you unziped it:
   1. SaRAcmd.exe -S OfficeActivationScenario -AcceptEula -CloseOffice
   2. SaRAcmd.exe -S ResetOfficeActivation -AcceptEula -CloseOffice
6. Then try to log in into your Office application. You may need to reboot your computer to make it work.

Source: SonicWall NetExtender 10.2.338 Release Notes, NetExtender Breaks Connection to Microsoft Services — SonicWall Community