To disable Windows 10 notifications on Windows 8 you can do this by adding the following registry key if it doesn’t already exist.  At the same time it is best to also disable Windows Automatic Upgrades.

Step 1

Open the Windows Registry editor.  This will vary depending on the version of Windows you are using.  In this example we are using Windows 8 / 8.1.  This can be done as follows:

1. Right click on the bottom left of the screen
2. Choose Run
3. Type regedit
4. Hit Enter

Step 2

Create the following key if it doesn’t already exist

HKEY_LOCAL_MACHINE \SOFTWARE\Policies\Microsoft\Windows\Gwx

Step 3

Create a new REG-DWORD registry value named DisableGWX and give it a value of 1

Step 4

Whilst in the registry editor navigate to

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\?WindowsUpdate\OSUpgrade

Step 5

Change the AllowOSUpgrade value to 0.  If the key doesn’t exist you will need to create a new DWORD key.