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You need to replace the files from the itunes library folder called itunes library, the xml file and the extras file and the genius files( basically all the files not folders) on the computer that isn't already synced. It will populate itunes with everything(even files that aren"t there. Just delete(from itunes) but don't trash the files. Then drag your itunes music back in and you're good to go.
 
You need to replace the files from the itunes library folder called itunes library, the xml file and the extras file and the genius files( basically all the files not folders) on the computer that isn't already synced. It will populate itunes with everything(even files that aren"t there. Just delete(from itunes) but don't trash the files. Then drag your itunes music back in and you're good to go.

im very confused.....with what u said above...can u simplify it for me?

i had to format my computer....and iphone was sync'ed to the old hard drive...

now i just reinstalled everything..and my iphone wont play any music....with the new hard drive...

how do i fix this?
 
holy cow...that sounds so confusing im lost

i dont have the itunes library file tho..

where is it?

i had to format my computer

You will find the itunes file in the itunes music folder. the default location is given below unless you have modified it.

Mac:
MacHD > Users > *Username* > Music > iTunes > iTunes Music Library.xml

Windows (Vista):
\username\Music\iTunes\iTunes Music Library.xml

Windows (XP):
\Documents and Settings\username\My Documents\My Music\iTunes\iTunes Music Library.xml
 
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