Difficulty: Moderately Easy
Step1
Enable security alerts from suspicious website links. Click the Microsoft Office button and choose "Excel Options." Choose "Trust Center," then click "Trust Center Settings" and select "Privacy Options." Make sure you have "Check Office documents that are from or link to suspicious Web sites" checked.
Step2
Select "Enable Content" on the message bar if your workbook has external content. Choose to unblock the external content when the security dialog box appears.
Step3
Access the Trust Center to view your security and privacy settings for Active-X controls, add-ins and macros. Click on the Microsoft Office button and go to "Excel Options." From there, go to "Trust Center" and then "Trust Center Settings."
Step4
Password-protect your workbook. You can choose to require a password before anyone can open or modify your workbook. Select "Tools" from the "Save As" dialog box. Click "General Options" and input your passwords in the designated area.
Step5
Set the VBA / Macro Security to determine how VBA code and XML macros are executed. Go to "Tools," then "Macros." Set the security setting to at least medium.
Step6
Protect your worksheet from unauthorized editing by using Worksheet Protection. This allows other people to view most of the worksheet, but only edit certain cells. Click "Tools," go to "Protection" and select "Worksheet Protection."