iTunes Match on Mountain Lion doesn't work on my 2012 MacBook Pro. I had Lion before, and iTunes Match worked fine. Now it disconnects and back every few seconds. I tried resetting cache, iTunes, turning on/off match, but nothing works. Now what?

I had this same exact issue ever since upgrading to Mountan Lion. iTunes Match had been stopping during the matching process and all of my matched songs from my other computer were greyed out and inaccessible.

By using a lead from this (or another) thread, I changed my network DNS settings. I changed my DNS to Google DNS (8.8.8.8 and 8.8.4.4) and the match process started working and finally uploaded my remaining songs. After quitting iTunes and starting it again, my greyed out items were able to be downloaded. Perhaps the DNS I was using from my ISP was not resolving some addresses correctly?

It's worth a try.

same here!! FRUSTRATING!!

FINALLY IT'S WORKING!!!!!! Thanks Ducky01 I tried what you said and changed my DNS setting to Googles public ones and iTunes Match seems to be working. It is still in the process of uploading my new music, but seems to be working ok. It has restarted a couple times during the process, but so far has uploaded probably 50 of my 75 songs added since the Mountain Lion upgrade and it hasn't errored out during the first step at all.

Here is good info on how to change your DNS settings.

https://developers.google.com/speed/public-dns/docs/using

Hopefully this fixes others problems as well as it is a very frustrating issue. Personally I have moved over to Google Play Music for my streaming as I think it is better, but my wife still likes to use iTunes Match.

Here match is stable. Using cable connection (slow pings, but Googles DNS) it works processing found songs. Uploading songs only work via 3G connection (iPhone tethered).

Still can't get it to work here. It's been like this for more than a week now.

Ever tried a different internet connection?

I've tried ethernet and wi-fi connections and it keeps looping Step 1

Did you also tried different internet provider? If the problem is provider related ike in my case) wifi or ethernet wouldn't make any difference.

If you mean changing the DNS settings then yes, I've tried that. I can try to reset the router, maybe that'll help

No I don't mean changing DNS.

I mean a totally different provider. I did this by tethering my Mac to my iPhones mobile provider. Only with that connection my iTunes match is able to upload non identified songs.

I've tried it and this works! I hope this bug get fixed soon, this solution works but waaaaay slower than my high speed connection

Great. Anyone who could do this test as well?

Somehow it all works fine again now through my normal ethernet connection. 😕 Maybe this trick clears some kind of bug?

I don't want to dissapoint you. Without repetitive tests you can't be sure at all.

I tried using my Verizon 4G Jetpack with my iMac instead of my wired connection through my local ISP. It did not work.