Hi there this is my first post,

I have a MB 2.0 C2D and have been happily using my Airport Extreme in 802.11n only 5.0ghz mode - until today.

After upgrading the Airport Extreme with firmware to 7.1, my MB was unable to detect the base station on 5.0ghz. I had to reconfigure and am now using 802.11n only 2.4Ghz with no problems.

Why cant I use 5.0ghz anymore?

Will 2.4 be slower/less range?