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The demo mode of Minecraft will show in these scenarios:

• You've not yet purchased Minecraft on that account.

• You've purchased Minecraft, but on another Mojang or Minecraft account.

• Your purchase has been refunded. If this is the case, you would have received an email.

First, check to see if your account has a copy of Minecraft by visiting account.mojang.com/me. If you don't see a Minecraft profile listed or available to redeem, you may be logging in with the wrong account/email. Please try logging in with another email addresses that you own. If you bought Minecraft several years ago, try logging in with your username instead.

Next, try fully logging out of the game launcher. On the launcher screen, click Switch User, then click Log Out. Then log back in.

There is no need to re-download or re-purchase the game unless you received an email stating that you were refunded.

See below for a more detailed breakdown of why an account would only be able to access the demo.