A family of Microsoft word processing software products for creating web, email, and print documents.
In the Customize Keyboard dialog box, verify that Ctrl+Alt+F is assigned to InsertFootnoteNow.
To display the dialog box, click File | Options | Customize Ribbon | Customize. Then click in the "Press new shortcut key" box and press Alt+Ctrl+F. Which command do you see at "Currently assigned to"?