New microsoft account on xbox one, can't use xbox 360

The problem is that I never linked my xbox 360 to my xbox live account, [...]. So I'm trying to link my xbox live account to my xbox 360, but all I get are error messages.

My account is linked to my xbox one without any problems, but in order to save xbox 360 game data on my xbox one, I have to download my/a xbox 360 profile, which I can't do because my profile won't connect to xbox live.

The problem is, since you used a Xbox One, your Microsoft Account is now already "occupied" with a Gamertag, so you can't use that Microsoft Account to bring your old Xbox 360 offline Gamertag online.

You COULD create a new Microsoft Account to bring your Xbox 360 account online, but you won't be able to access the savegames with your Xbox One account, as Savegames can't be transferred between accounts.

So depending on how much you already invested in your Xbox One account, you might try to bring your old Xbox 360 account online, and use that on your Xbox One, and start your Xbox One gaming history over, or you can abandon your Xbox 360 saves and just use
your old account on the Xbox One to download your previous Xbox 360 digital games, and start these over with your new Xbox One account.

Since it's not possible to merge Gamertag accounts, you will have to decide which account you wish continue to use for actual gaming, and which account you simply keep to claim license ownership for downloaded games.

PhoneticBoot,

Unfortunately at this time this action can't be completed using solely an Xbox One at this time. You will need to use an Xbox 360 and follow the

Microsoft Account Change Guide. If this is something that you would like to see added to the Xbox One please create a new thread in the Xbox LIVE Wishlist/Feedback stating
such. Thank you,

This is an issue with the market place and 360 games.

This can be an issue with a child account or trying to use Microsoft credits, some purchases may need to be created on the Xbox 360

https://answers.microsoft.com/en-us/xbox/forum/all/purchasing-xbox-360-marketplace-content-faq/fd3a2dae-8777-4e5c-8e76-00914501c2cf

Q: Can I use my Microsoft account balance to pay for Xbox 360 content on my Xbox One console or from Xbox.com?

A: You can't use your Microsoft account balance to pay for Xbox 360 content on your Xbox One console or from Xbox.com. In order for you to use your Microsoft account balance to pay for Xbox 360 content,
you will need to make the purchase from your Xbox 360 console.

: Can child accounts purchase Xbox 360 Marketplace content from a Xbox One console or from Xbox.com?

A: Child or teen accounts cannot make purchases in the Xbox 360 Marketplace on the Xbox One console or Xbox.com. In order for a child or teen account to purchase Xbox 360 content, it must be purchased from
an Xbox 360 console.

Actually it is impossible in Xbox ONE move a gamertag from one MSA to another MSA. This action only can do in Xbox 360 platform.

This is because Xbox ONE used an independent platform than Xbox 360 and this new platform not allows this change because Microsoft says that this action can have security issues to customers.

So, the solution to do this action is change your gamertag follow this guide in a Xbox 360 console and then use your new MSA with your gamertag in Xbox ONE console:

support.xbox.com/.../switch-gamertag-to-different-microsoft-account

What are you trying to but it with? Credit card? Microsoft credits? Are you on the 360 or Xbox one? If on the Xbox one you can't use Microsoft credit to buy 360 games.