My Mac has OS 10.8.5 "Mountain Lion" with Airport Utility 6.3.1. When I try to control my older Airport Express, it tells me "This version of AirPort Utility doesn’t support this base station." This Apple Support page (HT5022) says I should get AirPort Utility 5.6, but its installer says "Airport Utility can't be installed on this disk. The version of Mac OS X on this volume is not supported." So how can I control my Airport Express, if I can't use the new one and I can't install the older one? (Specifically, I would like to set its channel.)
MacBook
Pro, OS X Mountain Lion (10.8.5), 2.7 GHz i7, 8GB memory, 1 GB disk