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 encoding of Type 2 font characters to glyphs used in the document is missing or does not match the encoding in the font dictionary of the document.
How can I fix it?
Use a PDF creation product that correctly encodes and embeds all fonts. We recommend Solid PDF Creator Plus.
6.3.3.2 - ISO 19005-1 PDF/A Specification:
For all Type 2 CIDFonts, the CIDFont dictionary shall contain a CIDToGIDMap entry that shall be a stream mapping from CIDs to glyph indices or the name Identity, as described in PDF Reference Table 5.13.