This article was previously published under Q238765
This article has been archived. It is offered "as is" and will no longer be updated.
When you create an Outlook custom form solution that programmatically uses one of the following control properties, the form becomes a one-off:
When an item is a one-off, the typical symptoms include:
The size of an item may increase.
The message class changes to the standard message class for that type of item.
The "enable/disable" macro warning message may unexpectedly appear.
To work around this problem, use one of the following methods:
Avoid Using These Specific Control Properties
If you are designing a custom form solution that will be used by different versions of Outlook, including Outlook 2000, you may want to avoid using these properties so that Outlook 2000 does not create a one-off form.
Depending on the property that you are using, you may be able to use a different approach to achieve the same, or similar, effect. For example, if you are using the ReadOnly property, consider using the Enabled property instead. If you are using the PossibleValues property, you can use a different approach to populate the control. For additional information about how to populate a list box or combo box, please see the following article in the Microsoft Knowledge Base:
232341 OL2000: How to Populate a List Box or Combo Box
NOTE: There are no workarounds for the ItemProperty or LayoutFlags properties, as these properties provide unique functionality.
Programmatically Reset the Message Class of the Item
You can programmatically reset the message class of an item so that it continues to use the published form. For additional information about one-off forms and how to avoid them, please see the following article in the Microsoft Knowledge Base:
207896 OL2000: Working with Form Definitions and One-Off Forms
Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.
For additional information about available resources and answers to commonly asked questions about Microsoft Outlook 2000 solutions, click the article number below to view the article in the Microsoft Knowledge Base:
146636 OL2000: Questions About Custom Forms and Outlook Solutions