The reason your OCR fails is likely because the scan is dirty. Professionals do this:
Dirty backgrounds (shadows, coffee stains) and speckles (dust spots) confuse the OCR into seeing letters that aren't there. Cleaning first is the single most effective fix.
Most users don't know that Adobe includes a diagnostic tool. This is often the only adobe acrobat dc ocr fix you will ever need. adobe acrobat dc ocr fix
If quick fixes fail, you have a system-level or configuration issue.
If you have tried all 10 fixes and your PDF still looks like hieroglyphics, the Adobe engine cannot handle the file. You need a specialized OCR engine. The reason your OCR fails is likely because
If a PDF has corrupt OCR, you must strip the hidden data before re-processing.
For documents that have already been processed but contain typos or gaps, you do not need to re-scan the whole file. Acrobat provides a surgical tool. Execute the sanitization
Pro Tip: If the list of suspects is in the hundreds, do not fix them manually. This indicates a systemic failure (e.g., a rotated page or a stain on the scan). Fix the root cause (rotate/clean the image) and re-run the full OCR.
Steps:
If OCR is grayed out: