A personal Microsoft account cannot be converted into a work or school account. They are separate account types, and there is no synchronization between them.
To fix the sign-in issue:
- Sign out of the app or service where the wrong account was used.
- Sign in again and choose the correct work or school account.
- If the wrong account keeps getting reused, open a private browsing window and sign in there with the work or school account.
- If Windows is using the wrong connected account, go to Settings > Accounts > Access work or school and connect the correct work account.
- If the email address exists as both a personal account and a work account, the sign-in screen may show "Which account do you want to use?". In that case, select Work or school account.
If the email was accidentally set up as a personal Microsoft account and the app only supports organizational accounts, that personal account will not work for that application. A valid work or school account created by an organization administrator is required.
If the prompt keeps appearing because the same email address is attached to both account types, one way to reduce confusion is to rename the personal Microsoft account by changing its primary alias in Manage how you sign in.
If the work account cannot sign in or is not available, contact the organization’s IT admin.
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