Same problem here on two machines. Both run Windows 10, but one is a custom built desktop and the other an Asus laptop. Laptop is using the latest MB version, while the desktop is on 3.0.6. Neither of them will now permit web protection to be enabled nor will a scan actually scan anything (just starts and then dies around the 4 - 10 second mark). On the laptop I have:
Uninstalled MB.
Rebooted
Run the MB Clean tool
Rebooted
Reinstalled MB.
Rebooted.
This does NOT solve the issue (I have now done this three times). I do notice that the MBClean utility doesn't see