Hello
Is your Published form(Location) accessible to the users who are opening the
attachment? Infopath form when opens look out for the form template and
throws an error if the template is not found.
Read this link
http://office.microsoft.com/en-us/infopath/HP010968751033.aspx

Signature
Kalyan G Reddy
INFOPATH MVP 2007 and 2008
http://www.ggktech.com
> When sending the form as an attachment (the end user has InfoPath) it gives
> them an error that the form cannot be opened. What s it that I’m doing wrong?
> Outlook 2007 (attach form) send email
> User opens the email but cant access the form, now if I embed the form the
> user can see it.