Click on the Start orb
, then type cmd
in the Search Programs and files box.
CMD will appear in the results above the search box. Right click on it and then select Run as administrator.
When the Elevated Command Prompt opens enter the following commands one at a time. If you are promted for any confirmation click on OK.
netsh advfirewall reset
net start mpsdrv
net start bfe
net start mpssvc
If this has run successfully you should receive a message stating that it succeeded.
Restart the computer and see if you can now make changes to the setting for the firewall.