Problem:
AVI files saved on Mac OS X 10.8.2 do not play in QuickTime.
Solution:
When saving an AVI file on a Mac the produced file will prove incompatible with QuickTime X. It has been found that QuickTime X does not support many codecs that previous versions used too. Thus the solution is to use another player.
AVI files have been found to work properly on Mac OS X 10.6.8. Furthermore on Mac OS X 10.7.5 it has been found that using the non-compressed option will not work whereas using the line preserving method does work properly. Also to note is that these same files that do not work in Mac OS X do in fact play on Windows.