OCR is messing with Symbols and Pictures

[HessenMobil]

Hello,

we recently switched to Adobe Acrobat Pro 2017 since Acrobat Pro XI went EOL and our users ran into the following problem with the new version.

They need to edit text in existing PDF blueprints which contain a lot of icons and symbols with text in them.

So they use "Edit PDF" with OCR enabled and change some text.

Once the PDF is saved, the icons and symbols are also converted to text and with that ruined by the OCR.

I included one picture before OCR and one afterwards.

Is there a way to select only a part of the PDF to run through OCR or keep it from trying to convert anything else than plain text?

Our old Adobe XI did not have this problem.