Locking cells in an Excel spreadsheet can prevent other users from accidentally or deliberately changing the data in those cells. Once a cell is locked, it cannot be edited until it is unlocked. You can lock all the cells in a worksheet or specific cells in a worksheet. You can also unlock all the cells or specific cells in a worksheet. If you protect a worksheet, all the cells in the worksheet will be locked, but you can choose to unlock specific cells. If you protect a workbook, all the cells in all the worksheets in the workbook will be locked, but you can choose to unlock specific cells in specific worksheets.

To lock or unlock cells, you must have worksheet or workbook protection turned on. To turn on worksheet or workbook protection, do the following:

1. Click the File tab, and then click Options.
2. In the left pane, click Advanced.
3. Under Editing options, select or clear the Allow users to edit ranges check box to turn worksheet protection on or off.

If you turn on workbook protection, you will be prompted to enter and confirm a password. If you do not enter a password, anyone who tries to turn off workbook protection will be prompted to enter a password. If you forget the password, you cannot turn off workbook protection or unlock cells that were locked when workbook protection was turned on.

To lock cells or ranges, do the following:

1. Select the cells or ranges that you want to lock.
2. Click the Format button on the Home tab, and then click the Lock Cell button in the Cells group.

Locked cells or ranges are indicated by a locked padlock icon .

To unlock cells or ranges, do the following:

1. Select the locked cells or ranges.
2. Click the Format button on the Home tab, and then click the Unlock Cell button in the Cells group.

You can also unlock all cells in a worksheet by doing the following:

1. Click the Format button on the Home tab, and then click the Unlock Cell button in the Cells group.
2. In the Unlock Cells dialog box, click the Unlock All Cells command button.

You can lock all the cells in a worksheet by doing the following:

1. Click the Format button on the Home tab, and then click the Lock Cell button in the Cells group.
2. In the Lock Cells dialog box, click the Lock All Cells command button.

You can also unlock all cells in a worksheet by doing the following:

1. Click the Format button on the Home tab, and then click the Unlock Cell button in the Cells group.
2. In the Unlock Cells dialog box, click the Unlock All Cells command button.

You can protect a worksheet so that only unlocked cells can be changed, and you can specify a password that must be entered to unprotect the worksheet. To protect a worksheet, do the following:

1. Click the Format button on the Home tab, and then click the Protect Sheet button in the Cells group.
2. In the Protect Sheet dialog box, do one or more of the following:
3. To prevent other users from accidentally or deliberately changing data in cells, select the Locked check box.
4. To prevent other users from inserting or deleting rows, columns, or cells, select the Insert Rows, Insert Columns, or Insert Cells check box.
5. To prevent other users from changing the structure of the worksheet, such as adding or deleting worksheets, select the Structure check box.
6. To prevent other users from using features that can change the worksheet, such as sorting or filtering data, or using pivot tables or pivot charts, select the Windows check box.
7. To prevent other users from changing the worksheet theme or styles, select the Format Cells check box.
8. To prevent other users from making changes to objects in the worksheet, such as charts or shapes, select the Objects check box.
9. If you want to allow other users to make changes to specific cells, click the Format button, and then click the Allow Users to Edit Ranges command button in the Cells group.
10. In the Allow Users to Edit Ranges dialog box, click New.
11. In the Title box, enter a name for the range.
12. Click in the Refers to box, and then select the cells that you want to allow other users to change.
13. If you want to allow other users to enter a password to unprotect the range, select the Protection tab, and then enter a password in the Password to unprotect sheet box.
14. Click OK.
15. In the Allow Users to Edit Ranges dialog box, click OK.
16. In the Protect Sheet dialog box, do one or more of the following:
17. If you want to allow other users to select locked cells, select the Locked check box.
18. If you want to allow other users to select unlocked cells, select the unlocked check box.
19. If you want to allow other users to sort ranges, select the Sort check box.
20. If you want to allow other users to use Autofilter, select the AutoFilter check box.
21. If you want to allow other users to use PivotTable reports, select the PivotTable check box.
22. If you want to allow other users to use PivotChart reports, select the PivotChart check box.
23. If you want to allow other users to insert hyperlinks, select the Hyperlinks check box.
24. If you want to display a warning message when other users edit cells in a protected worksheet, select the Warn user when editing cells in a protected worksheet check box.
25. If you want to allow other users to use the worksheet, but not make changes to it, select the Allow users to edit objects check box.
26. Click OK.

You can protect a workbook so that only unlocked cells can be changed, and you can specify a password that must be entered to unprotect the workbook. To protect a workbook, do the following:

1. Click the Format button on the Home tab, and then click the Protect Workbook button in the Cells group.
2. In the Protect Workbook dialog box, do one or more of the following:
3. To prevent other users from accidentally or deliberately changing data in cells, select the Locked check box.
4. To prevent other users from inserting or deleting rows, columns, or cells, select the Insert Rows, Insert Columns, or Insert Cells check box.
5. To prevent other users from changing the structure of the workbook, such as adding or deleting worksheets, select the Structure check box.
6. To prevent other users from using features that can change the workbook, such as sorting or filtering data, or using pivot tables or pivot charts, select the Windows check box.
7. To prevent other users from changing the workbook theme or styles, select the Format Cells check box.
8. To prevent other users from making changes to objects in the workbook, such as charts or shapes, select the Objects check box.
9. If you want to allow other users to make changes to specific cells, click the Format button, and then click the Allow Users to Edit Ranges command button in the Cells group.
10. In the Allow Users to Edit Ranges dialog box, click New.
11. In the Title box, enter a name for the range.
12. Click in the Refers to box, and then select the cells that you want to allow other users to change.
13. If you want to allow other users to enter a password to unprotect the range, select the Protection tab, and then enter a password in the Password to unprotect sheet box.
14. Click OK.
15. In the Allow Users to Edit Ranges dialog box, click OK.
16. In the Protect Workbook dialog box, do one or more of the following:
17. If you want to allow other users to select locked cells, select the Locked check box.
18. If you want to allow other users to select unlocked cells, select the unlocked check box.
19. If you want to allow other users to sort ranges, select the Sort check box.
20. If you want to allow other users to use Autofilter, select the AutoFilter check box.
21. If you want to allow other users to use PivotTable reports, select the PivotTable check box.
22. If you want to allow other users to use PivotChart reports, select the PivotChart check box.
23. If you want to allow other users to insert hyperlinks, select the Hyperlinks check box.
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