Currently Being ModeratedJul 30, 2012 10:52 AM (in response to HELLOPLUM)
A quick forum search will find some that experience this and a solution.
Delete and redownload:
Currently Being ModeratedJul 30, 2012 10:59 AM (in response to HELLOPLUM)
Assuming you are in a region where you are allowed to redownload your past music purchases, delete the broken tracks from your iTunes library, go to the iTunes Store home page, click the Purchased link from the Quick Links section in the right-hand column, then select Music and Not on this computer. You should find download links for your tracks there.
If you don't see them straight away it may help to close and restart iTunes.
While downloading select Downloads in the left-hand column and make sure Allow Simultaneous Downloads is unticked.
If the problem persists, or that facility is not yet available in your region, contact the iTunes Store support staff through the report a problem links in your account history, or via Contact Support.
See also: HT2519 - Downloading past purchases from the App Store, iBookstore, and iTunes Store