Checking Out a Excel Workbook
If you have a worksheet wherein only one person should modify it at a time, you can check the Workbook out, preventing any other user from modifying the Workbook while you have it checked out.
How to check out a workbook
1. Start by clicking 'File' in the upper left-hand corner of your spreadsheet
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2. Then click 'Info'
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3. Then click 'Manage Workbook' and then 'Check Out'
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How to see if a workbook is checked out
To view if a Excel Workbook is checked out, you can see a little icon in Teams or a lock on the file itself in File Explorer:
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Alternatively, if you open the file in Teams or Excel online, it will show the document as locked when trying to make it allowed for edits.
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If opening the Excel application, you will see it open in Read-Only.
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