I received InfoPath cannot open the selected form, after migrating a form into Visual Studio and trying to debug the project (Preview Form).
I solved the problem, opening the xsf file and choosing to replace with the new version. The problem was related to the duplicate ID of the form.
If you reopen the project, it will work as expected.
PingBack from http://blog.a-foton.ru/2008/07/infopath-cannot-open-the-selected-form-after-moving-xsn-to-visual-studio-infopath-project/