In Office Calc you can protect sheets and the document as a whole. You can choose whether the cells are protected against accidental changes, whether the formulae can be viewed from within Calc, whether the cells are visible or whether the cells can be printed.
Protection can be provided by means of a password, but it does not have to be. If you have assigned a password, protection can only be removed once the correct password has been entered.
Note that the cell protection for cells with the Protected attribute is only effective when you protect the whole sheet. In the default condition, every cell has the Protected attribute. Therefore you must remove the attribute selectively for those cells where the user may make changes. You then protect the whole sheet and save the document.
These protection features are just switches to prevent accidential action. The features are not intended to provide any secure protection. For example, by exporting a sheet to another file format, a user may be able to bypass the protection features. There is only one secure protection: the password that you can apply when saving an OpenDocument file. A file that has been saved with a password can be opened only with the same password.
Select the cells that you want to specify the cell protection options for.
Choose Format - Cells and click the Cell Protection tab.
Select the protection options that you want. All options will be applied only after you protect the sheet from the Tools menu - see below.
Uncheck Protected to allow the user to change the currently selected cells.
Select Protected to prevent changes to the contents and the format of a cell.
Select Hide formula to hide and to protect formulae from changes.
Select Hide when printing to hide protected cells in the printed document. The cells are not hidden onscreen.
Click OK.
Apply the protection options.
To protect the cells from being changed, viewed or printed according to your settings in the Format - Cells dialogue box, choose Tools - Protect Sheet.
To protect the structure of the document, for example the count, names, and order of the sheets, from being changed, choose Tools - Protect Spreadsheet Structure.
If you forget your password, you cannot deactivate the protection. If you only want to protect cells from accidental changes, set the sheet protection, but do not enter a password.