This page suggests either trying System Restore or a different DNS server:
https://www.sevenforums.com/gaming/381705-internet-games-not-working.html
However, since the problem is on three different machines, I can't see how System Restore would be relevant. Further, I can't see how your choice of DNS server would make any difference but, even so, it
might be worth trying a different one. (It certainly can't do any harm):
Click Start
Click Control Panel
Click Network and Sharing Center
The 'View Your Active Networks' section is divided into two. Look for the link on the right-hand side, next to 'Connections'. (Mine is labelled 'Local Area Connection 2'). Click on it.
Click Properties
Click on Internet Protocol Version 4 (TCP/IPv4), in order to highlight it
Click Properties
Click the button next to 'Use the following DNS server addresses'
Fill in the 'Preferred DNS server' fields as 216 . 146 . 35 . 35
Fill in the 'Alternate DNS server' fields as 216 . 146 . 36 . 36
Click OK
Click Close
Click Close