I designed a editable PDF in Adobe LiveCycle Designer.
Customers complain that PDF does not open and displays the following message:
Please wait… If this message is not eventually replaced by the
proper contents of the document, your PDF viewer may not be able to
display this type of document. You can upgrade to the latest version
of Adobe Reader for Windows, Mac, or Linux by visiting
http://www.adobe.com/go/reader_download. For more assistance with
Adobe Reader visit http://www.adobe.com/go/acrreader.
I personally walked down to check and they are using the most recent updates too.
Figured it out.
Customer was trying to open editable PDF in browser.
Asked customer to download and then open. Works fine.