All current versions of Windows have IPv6, Windows Vista and Windows 7 come with it enabled by default. The world is moving towards IPv6, so this is good for the future, but currently most networks are still IPv4. When a computer wants to connect to another IPv6 and the ISP is ipv4 only, a virtual card is made to convert between these networks. Some computers develop this program where Windows can not remove these cards, and it keep making new ones. They are HIDDEN devices, under device manager, you must set show hidden devices to see them. Microsoft calls them “6to4 Adapters”.
So in this situation these cards keep being added to the system, and adding, and adding. Eventually the use will attempt to connect to a local server, or some other service, and Windows will try every virtual card first, and then fail to connect. Timing out, even though the real connection has no fault and is connected properly. It appears at around 180 virtual cards we start to see problems.
The solution is removing all the cards, but Windows wants you to remove them one at a time. Microsoft does have a tool for removing devices in a systematic order, but you need to get the one for your architecture, and some of these need you to download a large package and extract it. So I decided to make it simple, download and run my tool and it will remove these cards for the user. After the removal the user will need to reboot, but then they can connect.
Now this doesn’t keep the computer from adding more cards in the future, and I don’t want to disable IPv6 by default, for it is slowly rolling out and when the user actually gets it they should be able to use it. I did add the ability to run Microsoft’s suggested fix and disable IPv6, so you can either remove just the cards, or run the whole IPv6 disable part. The program also includes a IPv6 setting changer, so you can change your IPv6 setting when the time comes. This is also put out as a separate program.
The download link is below, it requires .Net 2.0, which is already installed on Windows Vista and Windows 7.