For each PDF/A-1 validation issue we try to explain what it means and, if possible how to resolve it. For a more technical explanation of the issue we quote the related section of the ISO 19005-1 PDF/A Specification.
The document does not specify a rendering intent or it specifies a rendering intent other than the four defined in the PDF Reference.
How can I fix it?
Open your PDF file in Solid PDF Tools and then File | Save As PDF/A. This will add the Default rendering intent of RelativeColorimetric to your PDF/A file.
6.2.9 - ISO 19005-1 PDF/A Specification:
Where a rendering intent is specified, its value shall be one of the four values defined in PDF Reference RelativeColorimetric, AbsoluteColorimetric, Perceptual or Saturation.
NOTE: The default rendering intent is RelativeColorimetric.