when I finished my step 2,it's just start over again,match my songs in the itunes store again and again,i just don't know how to fix it,there's almost 17000 songs in my itunes library.
Welcome to Apple Support Communities.
It sounds like you're experiencing some unexpected behavior with iTunes Match.
You may find this article helpful:
iTunes Store: Troubleshooting iTunes Match
ever figure out how to fix this? having the same problem!
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