This port is opened probably because you have Network Discovery enabled in a Public Network profile.
To make sure if this is the case, don't block it and disable Network Discovery for any public profile you may have.
Go to Control Panel\Network and
Internet\Network and Sharing
Center\Advanced sharing settings
Disable Network Discovery on your
Home Network and Public Network
(Not sure if you need a reboot)
Check your ports again. Should not be
opened.
Enable it in your Home Network and
leave it off in your Public Network.
If you are using Windows Firewall it will be correctly mapped and it won't accept connections from outside. Only from within your home network. If you are using a personal firewall, make sure it has port level access so that you can set it up to only accept incoming/outgoing connections from/to your home network.
Best Answer