On the Properties dialog for the folder, you need to make the custom form the default form for that folder.

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Sue Mosher, Outlook MVP
Author of Microsoft Outlook 2007 Programming:
Jumpstart for Power Users and Administrators
http://www.outlookcode.com/article.aspx?id=54
> Hi.
>
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> //Jon
Hi.
> On the Properties dialog for the folder, you need to make the custom form the default form for that folder.
I have done this and it all works fine when I create a new entry directly in
the published calendar. It fails when doing so from the "Group Schedule".
Maybe I used the term "group calendar" when I was supposed to use the term
"Group Schedule" ("Actions menu" - "View Group Schedules", or click the
Schedules button).
//Jon
> > Hi.
> >
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> >
> > //Jon
Sue Mosher [MVP-Outlook] - 13 Mar 2008 15:36 GMT
Yes, "group calendar" and "group schedule" are two entirely different things. I know of no way to force the Group Schedule dialog to use a custom form to create a new appointment.

Signature
Sue Mosher, Outlook MVP
Author of Microsoft Outlook 2007 Programming:
Jumpstart for Power Users and Administrators
http://www.outlookcode.com/article.aspx?id=54
> Hi.
>
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>> >
>> > //Jon