How to make an Excel file read only
You can watch a video tutorial here.
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When you have a file that contains sensitive information, it is better to make it a read-only file. Especially if the file needs to be circulated, this prevents viewers from accidentally making changes to the file.
Step 1 – Protect the workbook
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– From the File menu, select the Info option
– Click the Protect Workbook button and select Always Open Read-Only from the menu
Step 2 – View the result
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– Check that the Protect Workbook switch is on