New 360, Same live Account

Are you trying to attach you old email to a new profile that you are creating? if so that will not work you would need to select download new profile as apposed to create profile.

Are you Downloading Profile ? if yes what is the error message you are getting ?

Each 360 account can be associated with a Live account.

Currently I have:

old 360 account -> associated with my Live account but with the old gamertag

new 360 account -> associated with my Live account but with the new gamertag

The new account got created when I downloaded my profile using my microsoft sign in. The old account was associated with the same microsoft sign in but it didn't recognize my gamertag change. Now it won't let me sign in to live because it asks for my microsoft
sign in details. I'm guessing the sign in fails because it's trying to find the microsoft account associated with the old gamertag.

I either need to somehow transfer my saves over to the new 360 account so I can upload them to the cloud, or I need someway for my Xbox to realize that my gamertag changed on the old account so I can sign into live again with that account.

I'm having the exact same problem.

I got a new xbox 360 for Christmas. I plugged it in. I tried to log into my xbox live account (this account) and it says, "The Microsoft account is already associated with an Xbox Live profile"... I have NO IDEA what that means.

but it will not let me use my new xbox360. AT ALL!!!

Hi,

You'll have to use a new account as offline only (or local accounts) can't be converted to Xbox Live accounts on the 360.

As you've already signed up for a Microsoft account to post on these forums, you can download this same account for use on the console. You'll then need to buy a subscription.

support.xbox.com/.../change-xbox-live-gamertag

-This is what OP is talking about I believe, not news, you are able do the same on xbox 360