Hello meysam,
The option to customize the form is only available with SharePoint list forms. For form libraries, you must first design your form in InfoPath, and then publish to an existing or new Form library. The reason for this is that a list form is essentially operating on top of the SharePoint list, and is considered flat data. InfoPath library forms are much more complex, and are not limited to the promoted properties (columns) of the library. If you want to make changes to a form that has been published to a library, the form can be downloaded form library settings > advanced settings, and then re-published to the library.
Hope that helps!
Bre
Bre Huston
| Project Manager
Qdabra® Software / InfoPathDev.com / FormsQuo / 877.544.2389 main / 425.318.7843 direct
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