I'm left to guess this is a Dell. See if Dell has driver updates. Remember that many had those PRE-N devices and routers. What a mess.
I have a Intel(R) Centrino(R) Advanced-N 6250 AGN wireless adapter in a WIN 7 machine that connects just fine to the internet both wirelessly and wired....except it won't connect on n. We have a DLINK router that does a, b, g, and n. Another computer in the house is connecting on n, and mine is connecting on g (another computer can only do g so we can't make the router only n). 802.11n mode is enabled.
How do I make the adapter use n instead of g?