After switch from Intercept X to Windows Defender a problem with Sophos Connect has occured

Hi all,

Our customer has two Sophos XG firewalls in two different locations.

After Intercept X was removed from the clients and replaced by Windows Defender, the Sophos Connect VPN connection is not stable anymore.
First, Sophos Connect is connecting normally. But after some time, or sometimes immediately, the connection is not working anymore. You have to disconnect and connect again.

We tested also from an external client without Windows Defender and with Intercept X from a different tenant. The problem is not occuring on this client.

It seems, that there is a conflict between Sophos Connect and Windows Defender. 

The customer has already configured exceptions in Defender for Sophos Connect but there is no improvement. 

A case at Sophos Support is already opened but maybe someone in the community has an idea what could be wrong here?

Thank you!

Best Regards,

Added tags
[edited by: Raphael Alganes at 6:23 AM (GMT -7) on 26 Sep 2023]