Go to File > Info > Protect Document > Encrypt with Password. Type a password, press OK, type it again and press OK to confirm it. Save the file to make sure the password takes effect.

How to lock cells in Excel to protect your data. You can also unlock a range of cells and grant permissions to others to edit.

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Learn how to unlock your Microsoft account and resolve 'account has been locked' error message.

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Dynamic lock is a security feature that automatically locks your device when you are not around. It uses Bluetooth to pair with a phone, and locks the device when the Bluetooth signal drops …

Discover the step-by-step process to change or reset your Windows password if you've lost or forgotten it. This guide will help you regain access to your Windows account quickly and securely.

To lock your file so that other users can't open it, see Protect an Excel file. To protect certain areas of the data in your worksheet from other users, you have to protect your worksheet.

Open the sheet or workbook that you want to protect. On the Review tab, click Protect Sheet or Protect Workbook. In the Password box, type a password, and in the Verify box, type the …

Microsoft 365 includes a file protection feature that allows authors to mark a file as Final. This locks the file, preventing any further editing. You can easily turn off this feature in the Microsoft …