inSSIDer Office will give a Configuration Warning if access points on your network aren't set to standard (non-overlapping) channels.
In the 2.4 GHz band, there are 11 available channels (13 in some parts of the world), but only three of them don't overlap: 1, 6, and 11.
When networks partially overlap, they talk over each other instead of taking turns. This causes corrupted transmissions, which slows everything down for both networks. inSSIDer Office colors adjacent-channel networks in red.
When networks share channels, the politely take turns talking, which is much more efficient. inSSIDer Office colors co-channel networks in yellow.
Configure your access points to only use channels 1, 6, and 11 to eliminate adjacent-channel interference. This will improve reliability and performance in the 2.4 GHz band for you and all surrounding networks.