Updating to InDesign 2017 has created an issue with exporting form fields that were created in a document made by InDesign 2015 and converted to InDesign 2017 to PDF.
When the document is finished exporting and is opened in Adobe Acrobat DC (has been fully updated), the form fields will be visually 'missing.' (Cannot select/type in/etc)
The <Form> article still exists in the Tags menu. But instead of having the metadata I assigned it in InDesign 2015, it has been retitled "Object Reference - 49 - OBJR."
What's worse, this disappearing form field issue jumps around on subsequent exports. So, I can replace the fields that have disappeared and re-export, and other fields will have inherited the issue.
The only 'fix' I have found is deleting all form fields generated in InDesign 2015 and re-drawing them in InDesign 2017. Any other fix possible?
Try saving the file out of InDesign CC 2015 as an IDML file. Then open that in InDesign CC 2017. There could be corruption in the file.