Outlook 98 Forms

Hello, I have a question about VBA programming with Outlook 98 forms.

I recently created a form which contains a custom control, the Coyote Calendar Control, which is a freeware calendar similar to Microsoft's Date-Time Picker control.

A user who tried to open the completed form received errors related to the calendar control; it turned out they didn't have the control registered on their system.

Upon installing the control via its setup program, the user was able to open and use the form properly.

Is there a way to force Outlook to use controls on the form, or am I stuck with installing the control manually on all users' machines?

Thanks in advance for any info.