After update to latest software Ipod doesnt show music files iPhone 4

I recently updated to latest phone software. Since then I cannot sync the music files from my iTunes to my iphone.
The I tunes shows all the music files as synchronized in the phone summary
( memory bar shows that the music is downloaded to the phone) but when I go to
iPod on the phone it tells me:
No content - You can download music from iTunes.
I tried everything including restoring the phone to factory settings several times but to no avail.
In my country Itunes store is not available.
The software version currently installed on my phone is 4.2.1 and on my iTunes is 10.2
Thank you!
Inspirion 1520 Windows Vista