Microsoft Office has rolled out a new security update which has affected millions of users who use Excel for office automation. If you you see this error when you open Gantt Excel then simply follow these simple steps and you will be able to enable macros.

  1. Close the file. Right click on the filename in Explorer, Select Properties.

  2. Check the 'Unblock' button. Hit Apply.

  3. Reopen the file and you should see the 'Enable Macros' button.

Enable Macros and you should be good to go.