How to access an outdated apple id for itunes?

When I created my apple id, and downloaded a shitload of music, it didn't need to be an email address. It was linked to my email, but the id itself wasn't my email address.

Then I downloaded an update to both itunes on my computer and my iphone (BIG MISTAKE! DO NOT DO THAT!). Now, just to copy any music from one to the other, or just play any music, it says I have to sign in with my apple id.

I put in the password that I"ve been using for 999 nonillion millennia with no problem, and it suddenly, magically, isn't the right password. I tried resetting my password; however, it won't accept my apple id, it says an apple id has to be an email address. So, I created one that is my current email address, linked to my current email address, and included the email address I had at the time I created the old id.

Itunes works, and I was able to copy a playlist onto my phone. However, It will play only music that I had copied from cd's, nothing that was downloaded. Every time I try to either play a downloaded song or copy it onto my phone it does the same thing: It brings up a dialog box that says I need to sign on with my old apple id, and then won't accept my old apple id, saying that an apple id has to be an email address; I sign on with the new id that is an email address, and it goes back to saying I need to sign on with the old id, the very one it says is not a valid id.

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