Outlook provides no way to do that.

Signature
Sue Mosher, Outlook MVP
Author of
Microsoft Outlook Programming - Jumpstart for
Administrators, Power Users, and Developers
http://www.outlookcode.com/jumpstart.aspx
> How do I change the color coding and patern of the availability status for
> appointments in Calendar.
> Busy, Tentative, Out of Office, Free.
> I want to change the color coding.
> Regards