Windows 10 signed you in with temp account? Here's the fix.

[Windows Central]

Are you getting an account error message as soon as you sign in? If so, then Windows 10 likely signed you in with a temporary account. Here's how to troubleshoot the issue.
On Windows 10 after an upgrade, installation of a new monthly update, or antivirus setup, you may receive the "We can't sign in to your account" or "You've been signed in with a temporary profile" error message as soon as you sign in to your account. When this happens, then the system signed you in using a temporary account, instead of your original account, and any changes you make in this session will be discarded as soon as you sign out.

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