iTunes and incompatable files for the iPod

[Inkmonkey]

I've had my iPod for just over a week. I've synched to iTunes a few times. Each time I do so I get a warning that a specific song could not be synched because it's not compatble with playing on the iPod. Can't remember the exact wording.

I've deleted the listed song but the next time I synch it gives me a different song that's not compatable. So a couple of questions:

What types of files would play in iTunes but not the iPod? I thought all of my files were MP3s.

Is there a way of easily finding out (within iTunes) which files are not compatable so I can delete them all? Right now I have to wait until each synch to find out which song is not gonna synch to the iPod.

[wrldwzrd89]

I've had my iPod for just over a week. I've synched to iTunes a few times. Each time I do so I get a warning that a specific song could not be synched because it's not compatble with playing on the iPod. Can't remember the exact wording.

I've deleted the listed song but the next time I synch it gives me a different song that's not compatable. So a couple of questions:

What types of files would play in iTunes but not the iPod? I thought all of my files were MP3s.

Is there a way of easily finding out (within iTunes) which files are not compatable so I can delete them all? Right now I have to wait until each synch to find out which song is not gonna synch to the iPod.
MIDIs and any other files that QuickTime can play (due to a third-party plugin) will not play on the iPod. The easiest way to identify what kinds of music you have in your library is to add the Kind field to Library view in iTunes if it isn't there already, then sort by Kind. Anything that isn't "AAC audio file", "MPEG audio file", "Apple Lossless audio file", "WAV audio file" or "AIFF audio file" should be considered suspicious.

[Inkmonkey]

MIDIs and any other files that QuickTime can play (due to a third-party plugin) will not play on the iPod. The easiest way to identify what kinds of music you have in your library is to add the Kind field to Library view in iTunes if it isn't there already, then sort by Kind. Anything that isn't "AAC audio file", "MPEG audio file", "Apple Lossless audio file", "WAV audio file" or "AIFF audio file" should be considered suspicious.

Great advice!
Thanks muchly.