Windows 7 Lost Shares and Microsoft 6to4 Adapters

[billcat]

Has this happened to you? Suddenly, overnight, you've lost your shares in Windows 7, you can see them but you can't access them, not even from the primary PC where they reside. You check all your permissions and nothing's changed, everything seems perfectly the same as it did when your shares worked the night before but when you try to access them you get an 0x800704cf error - The Network Location Cannot Be Reached. You click on the troubleshooting link, but to no avail .. the troubleshooter cannot suggest a solution.

Check your device manager and see if you've got a plethora of redundant Microsoft 6to4 Adapter clones under Network adapters. You've got to check View and then enable Hidden Devices in the toolbar. Awhile back I found
nearly 300 of these Microsoft 6to4 Adapters! It's a known Windows 7 problem recognized by Microsoft. A further problem is that the solution MS offers doesn't work. Nothing works except to manually uninstall these things because they clone themselves every time you reboot your computer.

Most people aren't aware of the problem until it manifests itself by a loss of shares and then they're stuck with having to uninstall each of those adapters, one-at-a-time, unless they're lucky enough to be running a 32-bit version of Windows. You can use DevCon to mass uninstall them, but unfortunately DevCon (which came as part of the Windows Server 2003 Service Pack 2 Support Tools) doesn't work in 64-bit Windows 7, not even the 64-bit flavor that was written way back when and never updated for this lastest OS.

So do yourself a favor before you suddenly lose you shares: check your device manager and if you see those hidden 6to4 clones, uninstall them now, and keep uninstalling them until MS comes up with a real solution, provided they ever do.

[aasoror]

Do yourself a favor and disable the virtual wifi adapter.
Seriously, is the typical "home"/"small office" consumer expected to have multiple "wireless" networks to which he needs simultaneous access ?

Find your virtual wifi adapter and disable it, if you "really really" have use for this functionality (there is a reason Microsoft Research has killed this project back in 2005) just make sure you disconnect the virtual adapter before shutting down/restarting you win 7 machine.

[billcat]

Do yourself a favor and disable the virtual wifi adapter.

Ah, but there's the rub. I don't have a virtual wifi adapter and I never did. Disabling the 6to4 and uninstalling all instances of it does nothing. It just pops back up on reboot.

This is not an uncommon problem but has actually been around since Vista:

Take a look at this link.
There are others including examples I found on ms support on Bing where this issue goes unresolved.

In the above link read the posts starting with eisbaerke .. 4 posts down.

[scboley]

It has to do with bridging ipv6 to ipv4 addresses and I've only got a single instance of it showing on my system. I wonder if it's connected to certain types of adapters being installed to trigger the multiple instances.....hmmmmm weird.

[billcat]

All the suggested fixes don't seem to work on quite a few systems. Some suggest rolling back nic card drivers, installing new drivers, disabling ipv6 but nothing seems to get to the root of the problem.

MS pretends the problem doesn't exist.

[Doyle33]

6to4 adapter is a component used for transmitting IPv6 packets trough IPv4 network correctly.



In some scenarios, there will be a code 31 or code 10 error appearing beside this component. A possible reason is, the network adapter doesn’t support this feature. You may update the driver for your network adapter or chipset, and then try to uninstall and reinstall the this component.



To uninstall the component, right-click the item in Device Manager and select Uninstall.



To reinstall the component, in Device Manager, Action – Add Legacy Hardware – Next – “Install the hardware that I manually select from a list” – Network adapters – Microsoft – Microsoft 6to4 Adapter – Next – Finish the wizard.



If the steps above doesn’t solve the problem, your network adapter is not a supportive one for this component. You can completely ignore this error, if there isn’t IPv6 network deployed in the environment. The error won’t affect your system.