iPod sync problem

Thanks for your reply JackT44. Unfortunately I found no information dealing with my specific problem. I have checked all the ways in which these files might by synced but no luck. Having clicked on each one - there are now 100 files that will not sync, and getting them back on my iPod again I thought that it might be alright. I have even played some of them. They are on the iPod. Or at least they were. Now they have been removed. I cannot identify why these particular files are removed and not re-synced. I reset to factory settings and tried again. No recognition of these apple codecs again. I need to get them on today as I am away for a week. I'll just have to click them individually and keep on doing it until I can find the answer to the problem. I can only suppose that there is a button somewhere that I have not/or have clicked. Wish I knew which one it is.

Solved it. For some reason my iTunes folder location had been removed from my preferences. I do not know why. I do not remember doing that. I can only assume that the unsynced files were not recognised for some reason because they were added when I set the new location again.

Many thanks. Good to know there are people who know stuff out there willing to help.