- Go to https://outlook.office365.com/owa/?path=/classic
- Click on the Settings
- Click Mail
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3. Click General > My Account
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4. Click Clean up mailbox
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5. Select the Folder you want to Cleanup
Warning: this process will delete your mails permanently
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3. Click General > My Account
4. Click Clean up mailbox
5. Select the Folder you want to Cleanup
Warning: this process will delete your mails permanently