How to Lock an Excel 2003 Spreadsheet

1. Launch Excel and open the spreadsheet which you want to protect.
2. Click the 'Tools' menu, expand the 'Protection' submenu and select 'Unprotect sheet.' This step will allow Excel to reinitialize the protection of the spreadsheet. If the spreadsheet is password protected, you may have to type in the current password.
3. Click the 'Tools' menu again, expand the 'Protection' submenu and select 'Protect sheet.' The 'Protection' dialog box will open.
4. Click the actions which you wish to allow users to perform on the sheet in the 'Allow all users of this worksheet to' list. For example, you can allow users to create a new column but prevent them from deleting any existing columns.
5. Type the password you wish to use to protect the spreadsheet in the 'Password to unprotect sheet' field. Confirm your changes by clicking 'OK.'