To set up Microsoft Outlook subcategories

You can supplement Microsoft Outlook's built-in Categories field with your own Subcategory field.

Method #1

Add a new Subcategory field to a  folder like this: 

1. Open a Contact.
2. Click the All fields tab
3. Select User-defined fields in folder.
4. Click New.
5. Define your new field as follows:
   
   Name: Subcategory
   Type: Keywords
   Format: Text

The Keywords type allows you to apply multiple subcategories to each item. 

Method #2

Limitations

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