I'm doing a project converting historical pdf's to pdf/a format for archiving. I'm consistantly running up against problems with xmp schemas not being predetermined. This one in particular keeps giving me error messages when converting via Preflight, despite the fact that as far as I know it IS a predefined schema.
Unfortunately I can't find any way of deleting it, and have no luck with the Convert Document Metadata fixup. I'm using Acrobat 9. Any hints?