1. Close all instances of WINWORD.EXE. This may include OUTLOOK.EXE if you are using Word as your e-mail editor.
2. Back up all configurations and files.
3. Launch Word 2007.
4. Click the Microsoft Office button at top left, then click Word Options. The Word Options dialog box displays.
5. Click Add-Ins in the list on the left.
6. Locate the Author application add-in.
7. Choose the add-in type as COM Add-ins from the Manage drop-down menu and then click Go.
8. Uncheck the Author add-in (from the COM Add-Ins window) and then click OK.
9. Quit all Microsoft Office applications.
10. Launch Word again.
11. Click the Microsoft Office button at top left, then click Word Options. The Word Options dialog box displays.
12. Click Add-Ins in the list on the left.
13. Identify the Author add-in.
14. Choose the add-in type from the Manage drop-down menu and then click Go.
15. Check the Author add-in and then click OK.
16. Open an Author document and verify that Home is the first tab on the ribbon.