Archiving old documents, after scanning, redacting staple and other marks, can't save as PDF/a? wizard is no help?

I am scanning some old documents to be archived. These documents are marked up and I need to use the redaction feature. Then I need to make them searchable, after I do this, and

try and save them as PDF/A, I get the " doesn't fit the criteria for PDF/A, then I run the wizard, try to make it work, same answer???  Any suggestions, Thanks Wayne