Norton 360 (No VPN) reduce internet download speed

Hi all,

I noticed yesterday that my download speed had significantly decreased.
After reinstalling Windows 11 (clean install), I realized that this was due to Norton 360.
When I uninstall the software, my speed returns to normal.

The VPN is always disabled.

You will find below a speed test carried out today.

09/21/2025 11.02 am : Norton 360 installed.
09/21/2025 11.07 am : Norton 360 uninstalled.

Below are the details of my system configuration.

CPU : AMD Ryzen 7 5700X3D

GPU : Nvidia Geforce RTX 3070

RAM : 48,0 Go

OS : Windows 11 Pro 24H2 (26100.6584)

Browser : Brave v1.82.170 / Firefox : 143.0.1

I hope someone can help me resolve this issue.

Thank you.