How can I make Windows prefer my wired connection?

Looks like Windows (XP, Vista, 7) are supposed to do this automatically. Windows uses the lowest 'metric' connection. You can manually alter these metrics if it isn't working correctly, but in most cases, wired should be preferred over wireless automatically. Check the source below for more how-to and explanation.

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th3dude's answer is great but he doesn't mention a key point in the link he provided.

From the link that th3dude posted: http://blogs.technet.com/b/clint_huffman/archive/2009/04/19/windows-prefers-wired-connections.aspx

You should know that Vista made a change to how we handle existing sockets – after plugging in, connections will not be switched over, you must re-establish the connection in order to make use of a wired connection. For example, if you’re downloading something from a website and realize that it would go faster by plugging in, you’d have to cancel and start over after plugging in. This is a change from XP and 2003. Here is a good reference:

The Cable Guy Strong and Weak Host Models http://technet.microsoft.com/en-us/magazine/2007.09.cableguy.aspx

Which means that when I am on wireless at work in a conference room and then drop the laptop back on the dock, I have to disconnect (software) from the wireless connection OR disable (hardware switch) the wireless adapter to get back on the wired network.

Hopefully that helps you understand that it is probably not the 'metricing' that is choosing the wireless adapter but rather that Windows no longer auto-switches as it did in XP.

I'm not sure why Microsoft thought this was preferred behavior. I would have preferred a pop-up asking me whether to enable the wired adapter instead at the risk of ongoing downloads and sessions. Windows 7 makes me answer all kinds of other popups.

I tried every answer I could find but what worked in the end is me stumbling across right-clicking my wireless connection in the list of all available wireless connections (left-click up arrow near clock, then left-click on your connection, then right-click on the wireless connection you want to have available, but not be the default connect-to choice, and then clicking "Properties"). Under the "Connections" tab, uncheck "Connect automatically when this network is in range." This was even still necessary after changing the Metrics!

I know this question is rather old, but I found a solution that may work. Apparently, you can control this via scheduled tasks.

It involves using events generated by the LAN adapter when wired connection availability changes.

I haven't personally tested it yet, but I will after lunch and post back.

Edit: It was pointed out that I should include a more detailed answer. So with that in mind. You can open the event viewer in Windows 7 via Control Panel >> Administrative Tools >> Event Viewer. In Event Viewer, click Windows Logs >> System. With this open, unplug the ethernet cable and plug it back in. Press F5 to refresh the event listing. Click on the new events to see a description of them. There should be one referring to a network link being disconnected, and one referring to that link being re-established. Note the source and the event ID.

Now, open the task manager (Control panel >> Administrative Tools >> Event Viewer), and create a basic task. Name it something like "Switch to LAN" and click Next. Under Trigger, select when a specific event is logged. Click Next. Select the System log, and enter the event source and ID for the "Network being re-established" event. Click Next, and then select Start a Program. In the Program/Script section, type "C:\Windows\System32\netsh.exe". Then, in the Add arguments section, type 'interface set interface "Insert Wireless Network Name Here" disable' (make sure you include the quotes around the name of your wireless network). Click next and finish. Now when you plug an ethernet cable into your laptop, it will automatically disable the wireless network and switch to your LAN.

Now go and do the opposite in order to re-enable wifi when the cable is unplugged (type "enable" at the end of the script arguments). It should be noted, that this works on my Thinkpad W540 when the ethernet cable is plugged/unplugged. However, only the "Switch to LAN" functionality works with the dock.

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