Hi @rwhtx ,
If you use the developer tab to create a custom form, after creating the custom form, you need to save and publish it. You can save the form as a template or publish it directly to a folder. So there can be multiple forms in an account.
Additional documentation for your reference: https://www.guidingtech.com/how-to-create-a-custom-form-in-microsoft-outlook/(Note: Since the web site is not hosted by Microsoft, the link may change without notice. Microsoft does not guarantee the accuracy of this information.)
Besides, you can also use Visual Basic Scripting Edition to create custom forms. You can post with the "Office-development" tag, and the users of this forum will share their development knowledge so you can get more appropriate help.
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