For what? Publishing a form? Use olPersonalRegistry (2). To be precise use:
MyForm.FormDescription PublishForm
For accessing the actual personal forms registry you can't use the Outlook
object model. It's a collection of hidden messages in your PST or mailbox
that is only accessible using CDO 1.21 or Extended MAPI or Redemption code.
If that's what you are interested in let me know and I can show you some
code for accessing those hidden messages. If that's what you want you might
also want to download OutlookSpy from
www.dimastr.com since you will be
spending time looking at hidden messages and various MAPI properties.