What to do when iTunes says "This item cannot be downloaded"?

I had everything stored on my iPhone and to free up space I started storing my music in the cloud using iTunes match. "This item cannot be downloaded" is what pops up when I try to download different albums which I had originally uploaded to my computer from CDs I had owned. Now I can't download them from iTunes. I would normally just upload the CDs again to my computer but I've since sold them all. Any suggestions?

[Re-Titled by Moderator]

Original Title: This item cannot be downloaded