Set up an Excel file lock to prevent document editing

1. Open the desired Excel file or you can create an Excel file and save it. Then click the Review tab, and under the Change heading, click Protect Sheet

2. Then specify a password in the Password to unprotect sheet field, then click OK.

3. After that, you will be asked to enter your password again for confirmation. When finished, click OK.

4. You will then notice that the Protect sheet has changed to Unprotect Sheet. The next step is to set not to add a Workbook or add a Sheet by clicking on Protect Workbook (workbook protection).

5. Specify a password in the Password (Optional) field. When finished, click OK

6. Enter your password again and click OK

7. When finished, save the file, then close and open the file again. This will see that the file cannot be edited. It can only be read.

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