Hi Daniel,
Thank you for posting in Microsoft Community.
Error code 651 usually occurs when user tries to connect it’s broadband in windows 7 operating system.
It shows a message that Your modem (or other connecting devices) has reported an error and Usually the message will be “Connection failed with error 651” .
I suggest you to uninstall the Modem and check if it helps.
You can also do a right click on the Connections, Select Properties, Then Uncheck the box which says Internet Protocol Version 6 (TCP/IPv6).
Hope this helps. Please reply to us with the status of the issue.
Thanks.