When I'm at my desk at home, I connect to my network through my Ethernet LAN port. Sometimes however I have to get up and move my computer around (such as to connect it to a TV in another room), so I disconnect the Ethernet and enable the wifi. My problem however is that I want both the LAN and wifi interfaces to have the same static IP address in my network. Everything worked perfectly on Linux: I could set both interfaces to the same IP, same subnet mask, same default gateway, and same DNS provider. If I had Ethernet connected and wifi enabled at the same time, I would get martian packet messages in the system log, so I would just use the physical switch on the laptop to disable the wifi interface until I needed it.
However, recently I've been configuring a new laptop that runs Windows 7. I wanted to do the same thing as I could do on Linux on the other laptop. After setting the static IP address, subnet mask, gateway and DNS for the Ethernet interface, I tried to do the same thing for the wifi interface, but I got first the warning that another interface already has the same IP address, and then I got the message about multiple default gateways as being intended to provide redundancy. I dismissed both warnings (No, then Yes) and clicked Close. But when I opened up the properties for the wifi interface again, the IP address and subnet mask fields were blank. Everytime I enter them, they are blank when I reopen the properties page. The Ethernet interface's properties page still has the same information.
So basically my question is, how can I set this up properly without Windows blanking out the settings for the wifi interface? If it can work properly in Linux, why can't it work here?