Sophos NAC: computer displays a blue screen when you remove the PacketTrace registry key from a computer running the NAC Agent and restart the Agent

Issue

The computer displays a blue screen when you remove the PacketTrace registry key from a computer running the NAC Agent and then restart the Agent.

Sophos product and version

Sophos NAC version 3.1

What to do

Add the logging key to HKLM\SOFTWARE\Sophos\NAC\
Add the PacketTrace dword and set the value to 1.
Stop the AgntTray and AgentAPI services using Administrative Tools > Services to enable packet tracing.
Start the AgntTray.exe.
Complete packet tracing.
Stop the AgntTray and AgentAPI services using Administrative Tools > Services. Using Windows Task Manager, wait for the AgentAPI.exe process to complete. If you do not wait for the AgentAPI.exe process to complete, the computer may blue screen.
Delete the PacketTrace key from the registry.
Start the AgntTray.exe or restart the computer.

If you need more information or guidance, then please contact technical support.