The following was posted on Tom's hardware and many other places on the internet.....neither works for me!
Turn USB notifications on or off in Windows 10 using the registry
1. Open Regedit.
2. Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Shell\USB.
3. Modify ‘NotifyOnUsbErrors’ to ‘0’ to turn off and ‘1’ to turn on.
You can also change the notification within the settings menu.
Turn USB notifications on or off in Windows 10 in Settings
1. Navigate to Settings within Windows 10.
2. Select Devices and then USB.
3. Toggle the setting on the right on or off to change notifications.
Turn USB notifications on or off in Windows 10 using the registry
1. Open Regedit.
2. Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Shell\USB.
3. Modify ‘NotifyOnUsbErrors’ to ‘0’ to turn off and ‘1’ to turn on.
You can also change the notification within the settings menu.
Turn USB notifications on or off in Windows 10 in Settings
1. Navigate to Settings within Windows 10.
2. Select Devices and then USB.
3. Toggle the setting on the right on or off to change notifications.