Protecting the document means that without the password a user cannot add
or delete sheets. Document protection does not protect cells.
Select
->
.
A dialog appears asking you for a password. The
Password:
strength meter
indicates if your password is secure enough. The longer the indicator is, the
more secure your password.
That password will then be required to unprotect the document.
When a document is protected, you may not:
Protecting a sheet means protecting the contents of all protected cells
and objects on a sheet. Individual cells or a selection of cells can be
unprotected within a protected sheet, see next section.
To protect a sheet, select
->
.
A dialog appears asking you for a password. The
Password
strength meter
indicates if your password is secure enough. The longer the indicator is, the
more secure will be your password.
That password will then be required to unprotect the sheet.
When a sheet is protected, you may not:
-
Insert any object or chart
-
Format any cell
-
Insert a row or a column
-
Edit and change cell content
-
Change any content in the sheet
Note
Protecting a sheet is especially useful for preventing accidental
erasure of formulae.
Cell or selected cells protection
Warning
Cell protection is active for all cells by default and is
effective when you enable sheet protection. So if you keep the default and if
you protect the sheet, all cells will be protected.
If you want only certain cells to be protected, this default protection
must be turned off for all other cells. For example you might want most cells
to accept user input so you will uncheck
Protected
for
those and choose to keep protected cells that should stay unchanged (such as
titles). So you need 3 steps in order to protect only some cells: unprotect all
the cells, select the cells to protect and protect them and then protect the
whole sheet.
To unprotect all the cells:
-
Select the entire spreadsheet with the mouse.
-
In the menubar, select
->
.
-
In the dialog that appears, go to the
Cell Protection
tab.
-
Check
Hide all
and uncheck
Protected
to remove the protection on all cells. The cells are now all unprotected.
To protect a range of selected cells or a selection of non-contiguous
cells:
-
Highlight the range of cells that are to be protected or use the
Ctrl
key to select non-contiguous cells.
-
When all of the desired cells are selected, go to
the
->
menu.
-
In the dialog that appears, go to the
Cell Protection
tab.
-
Click on the box next to
Protected
then click
on
OK
.
Once the cells are marked for protection, the protection option must be
enabled at the sheet level, that means you must protect the entire sheet for the
cell to be effectively protected:
-
Select
->
.
-
In the dialog that appears, provide a safe password, then confirm it by typing
it again. Click on
OK
.
-
Protected cells in a protected sheet cannot be edited without unprotecting the
whole sheet, and any sheet changes are disabled. For example, no one can
insert rows or columns, change column width, or create embedded charts.
You might want to hide your formulae so other people cannot see
them. By default, every cell is protected and not hidden. But it is important to
remember that these attributes have no effect unless the sheet itself is
protected.
To hide cell formulae, select the appropriate cell or range of cells or
non-contiguous cells with
Ctrl
and
then choose the
->
menu. In the Cell format
dialog, click the
Cell Protection
tab and select
Hide formula
.
After you protect the sheet, the results of the formulae will be visible, but
the formulae will not.
You have now to protect the sheet: choose
->
to display the
Protect Sheet
dialog box. Enter a safe password twice to prevent
others from unprotecting the sheet.
When
Hide formula
is enabled and
Protected
is disabled, the formula is hidden after
protecting the sheet but the cell content can be changed.
When
Hide formula
and
Protected
are enabled, the formula is hidden after protecting the sheet and the cell
content cannot be changed.
Keep in mind that it is very easy to break the password for a
protected sheet so if you are looking for real security, this is not the
best solution.
You can hide both the formula and the content of the cell by
choosing
Hide all
in the Cell Protection tab in the
->
menu. In the screenshot below, the
cell itself is not protected (
Protected
is unchecked) thus
the cell content can be changed.
Here the cell itself is protected so it cannot be overwritten.
