How to Protect Excel Cells From Modification

1. Start Microsoft Excel and open the file you want to change.
2. Drag mouse and highlight the cells you want to protect.
3. Open the Format menu and select Cells.
4. Select the Protection tab.
5. Click the Locked option.
6. Select OK to accept the changes.
7. Open the Tools menu and select Protection, then select Protect Sheet.
8. Click OK.