Apple Fixes Disappearing Base Station Issue with AirPort Utility 6.3.1

Apple released AirPort Utility 6.3.1 on Thursday, an update that fixes an issue, "where AirPort base stations may not appear in AirPort Utility." The patch notes don't include any other specifics.

You can download the update through Software Update or under Updates in the Mac App Store. You can also download a standalone installer (21.44MB) from Apple's support site.

Airport Utility

AirPort Utility