some music wont delete from iphone 4

When I sync my phone to iTunes to change music over there are nearly 500 songs that are greyed out and cannot be deleted or played. I would like to get rid of them so I have more capacity. I use an iphone 4 on OS 7.1.2


howapple - hello


If you loaded those songs there by syncing from iTunes - that is how you get the off

Create a folder on the computer and put one song in it

Connect phone to iTunes and sync music using that folder you just created

That should erase the prior songs