To open a form, the user has to be able to access the form template (.xsn)
file that is referenced within the InfoPath XML document. You can open the
XML file in Notepad and look at the ?mso-infoPathSolution processing
instruction to see the URL that the form is currently referencing.
For external users to open the form, you will need to publish the form
template to a URL on a web server that is accessible externally, then use the
same URL when you launch the template to fill out the form and mail it.
Alternatively, you can create an installer package for the .xsn file and send
it to your external users to install on their machines.

Signature
David Dean
Sr. Member Technical Staff
Insource Technology Corp.
> The user cannot open the file even though he has Office 2003 with Infopath on
> his computer. He gets the following error message: Microsoft Office InfoPath
[quoted text clipped - 19 lines]
> > > template, add information to it and return it to me?
> > > thanks for your help! =)
monica - 03 Aug 2007 20:36 GMT
Hi David,
thank you for your response. what is an installer package for an .xsn file?
> To open a form, the user has to be able to access the form template (.xsn)
> file that is referenced within the InfoPath XML document. You can open the
[quoted text clipped - 30 lines]
> > > > template, add information to it and return it to me?
> > > > thanks for your help! =)