Windows Product Activation uses the following ports:

For Windows Product Activation to succeed, configure firewalls or other devices that are between the client and the Internet to allow traffic to pass over ports 80, and 443.

You can use Microsoft Internet Explorer or other Internet browsers to test connectivity through these ports.

To test whether port 80 is open:

1.	Open Internet Explorer.Type http://www.microsoft.com:80 in the Address bar, and then press ENTER.
2.	Type http://www.microsoft.com:80 in the Address bar, and then press ENTER.

To test whether port 443 is open:

1.	Open Internet Explorer.Type https://www.microsoft.com:443 in the Address bar, and then press ENTER.
2.	Type https://www.microsoft.com:443 in the Address bar, and then press ENTER.

If you can access the Microsoft Web site each time, ports 80 and 443 are accessible.

If your browser displays an error message such as "connection timed out," the corresponding port may be blocked.