Currently Being ModeratedFeb 7, 2013 10:56 AM (in response to alduberas)
I had this problem, but if you click on the itunes next to the Apple and chose preferences, so to the store and check the box that says "Show iTunes in the Cloud purchases" the music will reappear.
It seemed to turn itself off somehow, but at least it came back.
Hope this helps.
Currently Being ModeratedFeb 7, 2013 9:36 PM (in response to alduberas)
Christine has the right answer for you.
There are two different services in play here. iTunes in the a Cloud and iTunes Match. Neither one requires the other.
iTunes in the Cloud is a service of the iTunes Store which allows you to re-download your past purchases. iTunes 11 integrates this service directly into the iTunes browser so you can see any past purchases not on your computer or not hidden in the purchase history. However, the option to see these purchases sometimes gets turned off in the prefs if the Internet connection is interrupted and you need to re-enable it.
Currently Being ModeratedFeb 9, 2013 1:40 AM (in response to christine58)
I am having to constantly re-turn this **** thing on. I consider this to be one of the many bugs in 11.
Currently Being ModeratedApr 2, 2014 9:07 AM (in response to HACKINT0SH)
The solution that worked for me was that my music was located in Hidden Purchases. When I selected UNHIDE ALL, they re appeared in the cloud