InfoPath Dev

I have a working, published form, but if I change anything in it, the form will not open. I tried saving to a new source folder, created new nsn file, etc. No good.

 The form works fine until I go into the designer and change anything. Then it will not open for preview or otherwise. Checker says: No error

 I can actually still publish the changed form, but it will not open. I asked others to try it,, Same problem. No errors, it just sits ther: Opening Form.....

How is the versioning set on the template? Do you get any error when you try to open?

No errors when attempting to open initially or after any modifications. If I make any change at all, the preview just hangs with a message at the lower left saying:

Opening Form.... <--- Hangs right here

It looks like any change to the form requires the form to be re-compiled and it cannot resolve something. There are no error indications, no posts, nada. Form Checker is clear

What's strange is something has changed since I have modified this form several times in the past and re-published without problems. If I re-publish this same form without any changes, no problem. I have went back to old forms and do not have any problems until a change is made. I am running InfoPath 2007 with the latest patch on Vista.

It wouldn't be so bad if there was some indication, pop-up, error message or something that provided insight.

 I went to a known working form and attempted the same thing on another user's PC... Same Problem

That's just odd. Can you preview the form when you have it in design?

I found out that if I change the security default level to restricted, the form opens but without content for items that need network input. I tried using domain and placing what I think is the domain for previewing, but nada. Maybe the company change some networking security stuff and now my forms no longer open. Just a guess...

Preview works until I make any change to the form. What's funny is, I went back to the first form that always worked for me and I get the same problem.

I rebuilt the form from scratch... The new form works okay... Thanks for all your help :-)  Who knows what happened

 You might have been onto something re: the recompiling - you may have tried the 'Extract Form Files' function in the File menu and checked out what 'included files' were there - or other stuff - redundant now that you've rebuilt it, but the problem may have been more obvious after extraction.