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 0 font characters to glyphs used in the document 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.
6.3.3.1 - ISO 19005-1 PDF/A Specification:
For any given composite (Type 0) font referenced within a conforming file, the CIDSystemInfo entries of its CIDFont and CMap dictionaries shall be compatible, as described in PDF Reference 5.6.2; in other words, the Registry and Ordering strings of the CIDSystemInfo dictionaries for that font shall be identical, unless the value of the CMap dictionary UserCMap key is Identity-H or Identity-V.