File with an .XSN extension contains many different form template files in the CAB compressed file, utilised by Microsoft InfoPath software. There is an option to extract only specific files from such InfoPath archive.

MS InfoPath software can be used to design and create forms and it enables storing a scheme XSD file and XLS style sheet, characteristic to a given form, including Visual Basic and Java scripts and image files, in a single pack with the XSN extension.