Make sure all firewalls that you have for security have the ports forwarded.
Some spots to check are your main router or modem. If you have a router within a router then port forward the ports on the router your computer is getting its internet connection from.
Then check any antivirus software (sometimes they have firewalls built into them and make sure the ports are open there as well.
Then after that if you have Windows Firewall Enabled port forward the ports through there as well.