itunes won't play music from ipod

[nrsgzz]

hi.
this is the problem I have when I try to connect my ipod to a pc other than the usual one.
itunes detects it perfectly (windows doesn't) and I am able to see all the music and the playlist I have on it.
but when I try to listen to those songs or add new files to the ipod nothing happens.
this is the screenshot of itunes I took, see the "!" symbols on the left side:

http://storage.andreagozzi.com/images/itunes.jpg

also when trying to access the ipod with podutil doesn't work saying the ipod is not in disk mode.
any clues for both problems?

[honeybee1236]

-Go to Edit>Preferences>Advance and make sure iTunes is pointing toward the correct folder where your music is stored.
-Did you delete the songs from your hard drive or move them to another location on the HD? iTunes is unable to find the songs that's why the "!" are next to the songs.

The songs must be on your HD for you to access and use them.

[nrsgzz]

actually the files are not on the hd of the computer.
but does this forbid as well the transfer of new songs to the ipod?