When attempting to add XMP data to a PDF file produced with the "Microsoft Print to PDF" (Windows standard feature), ExifTool reports
Info object (n n obj) not found at offset nnnnnn
This can be reproduced with the attached (zipped) PDF file and the following command line:
exiftool -overwrite_original -v -xmp:description="Test" "test.pdf"
This works for me with the current version of ExifTool. This should have been fixed with ExifTool 11.94. Try updating your version.
- Phil
Oops, sorry.
I can't keep up. I'm still using the .93 release, which is only 3 weeks old ;)