I've created a document in Adobe X Pro and saved it as a Reader Extended PDF with Enabled Commenting & Markup. Most users are having no problem adding comments (by attaching a file) but I have a few users having issues (one with Adobe Reader 9 for Mac and one with Adobe Reader X for Windows). They are seeing the bar at the top telling them they cannot save data in the form, and they do not have access to any of the commenting or markup features.
Thoughts?