Where to find ADO Ext. 2.5 DDL and Security

I recently converted my VB program to use access 2000 and thus moving from DAO to ADO. The computer i was using had the ADO Ext 2.5 DDL and Security referenced. When I moved my program to another computer for further development the reference was missing. Both computers were win98se with VB6+sp3. Is it possible I installed the patch wrong?

May be you can download it from Microsoft Universal Data Access Web Site.

Thank you kindly, it fixed everything i needed.