iTunes 11: Repeated logins, tons of missing music and playlists

[PaperQueen]

To be honest, I'm not sure what the culprit is---iTunes 11, Match, or both.

Prior to upgrading to iTunes 11, everything worked fine on my MacMini (office). Immediately after upgrading, iTunes forces me to do the following every single time it launches:

1. Enter my Apple ID and password
2. Store > Turn on iTunes Match > Add this Computer > enter Apple ID

It then goes to the iTunes Match step-1-step-2-step-3 screen, but doesn't get past step 1. The status bar reads "iTunes Match - Sending information to Apple" for an indefinite amount of time (has been at that step for nearly 10 minutes this go around).

One time, I was able to get all the way to the screen that says "Your iTunes library is now available in iCloud," but Playlists are either empty or stripped down to bare bones. For example: My favorite playlist includes 42 songs, but only the 7 physically ON this machine appear. Last night, all 42 were visible, including those in the cloud.

More than 3/4 of my playlists are missing.

More than 95% of my music is missing.

My guess is that iTunes 11 isn't shaking hands with Match properly. but....for two hours last night, it worked. All playlists were there. All songs were there (well...all but one that I know of, but that, I'll dig into later).

Today? Messed up.

I've quit/re-launched five times. Have flipped Match off/on at least that many times. Still, missing playlists, missing songs. I have NOT launched iTunes on my Air or launched Music on the iPad or iPhone, afraid that once they sync, things will be even worse off.

Ideas, anyone?

[Inopia-Vi]

Seems like an iTunes match issue. Even with match, I'd keep a backup if I were you...just in case.

When I did try match, I had similar issues. I don't think its iTunes 11.

[8CoreWhore]

I don't have Match, but I get the repeated logins as well. Really Apple?