Lock all cells
If you take this route, Excel locks all cells on your spreadsheet. However, locking cells has no effect until you protect the spreadsheet too. Here’s how to do both.
Step 1: Select all cells on your spreadsheet by pressing Ctrl + A on your keyboard.
Step 2: Right-click on one of the cells, and then click on Format Cells. You can also press Ctrl + 1 on your keyboard to perform this step.
Step 3: In the window that pops up, look under the Protection tab to verify that all cells are locked by making sure that the Locked option box is checked. Click on OK.
Step 4: With all the cells selected, go to the Review tab from the toolbar at the top. Then click on Protect Sheet.
Step 5: In the window that appears, enter a password to protect your worksheet in the blank space provided. All the selected cells are now locked and protected.
Lock specific cells
You may want only certain cells to be locked on some of your projects. Here’s how to lock specific cells in your spreadsheet.
Step 1: If you have any locked cells from previous locking attempts, you need to unlock all the cells first. Start by selecting all cells by pressing Ctrl + A on your keyboard.
Step 2: Right-click on one of the cells and click on Format Cells, or just press Ctrl + 1 on your keyboard.
Step 3: In the window that appears, uncheck the box under the Protection tab that says Locked. Click on OK once you’ve done that.
Step 4: Select the cells that you want to lock on your spreadsheet.
Step 5: Right-click on one of the cells and click on Format Cells, or just press Ctrl + 1 on your keyboard.
Step 6: In the window that pops up, check the box that says Locked under the Protection tab.
Step 7: The cells you selected are now locked but not protected. Go to the Review tab from the toolbar at the top and select Protect Sheet.
Step 8: In the window that shows up, enter a password in the blank field provided. You have now successfully locked and protected the cells that you selected.
Source: Digitaltrends
