InfoPath Dev

I had been searching for a few days, but not until I was selecting tags for my first post did I find a helpful tag that pointed to this previous thread: http://www.infopathdev.com/forums/p/15981/56419.aspx Is there something specific to look for in the .xsd that could be a dead giveaway as to what's wrong?

I created a form about a year ago and published it to a SharePoint site, and every so often I apply a few updates. During my latest update, I made a few changes in the view1.xsl file within the .cab folder. The changes are visible in the form itself if I simply open it to fill in, but when trying to enter design mode, I get the following ...