Canon i-SENSYS MF729Cx Important Safety Instructions And Installation Manual page 305

register them again.
If you registered a destination that was specified from the Address Book and then delete the destination entry in the Address
Book, the destination is also deleted from the favorite scan settings.
Recalling Favorite Settings
Simply select the setting combination that suits your purpose from the favorite settings.
<Scan> <Favorite Settings>
Once you have recalled the settings, the setting combination, you can also change the scan settings as needed.
LINKS
Convenient Scanning with a Machine-Based Operation
Select the setting combination to be recalled