My Windows 8.1 laptop, fitted with an Intel Centrino Ultimate-N 6300 AGN wireless adapter, suddenly stopped automatically connecting to my router a few months ago. I attempted to connect wirelessly to multiple other routers, all to no avail. My laptop could only connect through an ethernet cable/tethered hotspot. I then moved houses and got the internet set up on a new provider and suddenly my laptop could connect wirelessly again! Sadly, after trying to connect to my university's wi-fi, I found out that the laptop wasn't fixed, it was simply able to connect to my new 5Ghz internet but still had trouble connecting to 2.4Ghz access points.
I've tried everything I can to fix this as my laptop is too vital to my studies for me to be without it even for a short period of time, therefore sending it off for diagnostic and repairs is out of the question for now. So far I have tried:
Installing the latest Windows 8.1 drivers for the card (currently on v.126.96.36.199)
Replacing the wireless card with a new one (same make and model)
A complete, fresh re-installation of Windows 8.1
Running out of ideas on what to try and so turning to the community for help. Even if you're not sure of a fix, determining the problem itself would also be a big help. Thanks much in advance!
I had a similar problem, except mine card would not connect to 5ghz. I searched around the net and it said update your drivers, so I did to 188.8.131.52 now it only connects to 5Ghz and not 2.4Ghz just like your problem. I tried rolling back and it didn't help create the original problem it's stuck only being able to find 5Ghz channels.