Hi @Rujia Wang ，
If want to switch to another Outlook email profile, you can follow the steps:
- Open Outlook and select File > Account Settings > Change Profile.
- Outlook will close. You’ll need to start Outlook again manually.
- The next time Outlook starts, it will display the Choose Profile Dialog.
- In the Choose Profile dialog box, in the Profile Name list, click the profile that you want to be the default.
- To show this dialog every time Outlook starts, select Options > Prompt for a Profile to be used.
If you want to change the email for your Microsoft account, please refer to the following link: Change the email address or phone number for your Microsoft account
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