I have a Adobe Acrobat Pro XI. My client has Adobe Acrobat Pro X. In XI, my documents are completely accessible, but when they run the accessibility check in X they show errors. The client will send documents back to us as non-compliant due to these errors and ask that we fix them. Unfortunately, we are not able to see these errors on our side, so it is very hard to try and fix. Is there a way to run the X accessibility check in XI, so that we make the document as compliant as our client is expecting?
When you run the Accessibility Check in XI, are all of the Checking Options selected, other than "Tables must have a summary"? What specific errors are being flagged in X but not XI? (it might be helpful to ask your client to create and send an Accessibility Report)
Another approach would be for you and your client to agree to standardize on one of the free PDF Accessibility Checkers from the Swiss foundation Access for All: PAC 1.3 for WCAG 2.0 compliance or PAC 2 for ISO 14289 (PDF/UA - Universal Accessibility) http://www.access-for-all.ch/en/pdf-lab/pdf-accessibility-checker-pac/downloading-pac.html.
Both PAC checkers are much more thorough than the checkers built into Acrobat X and XI.