Acrobat will write ü instead of 0 when I edit a PDF.

I had the same thing happen, but for me it was the "o" that appeared as the Umlaut "ü."  I first installed the German spell checker but that didn't change anything.  I then turned off the option "Recognize Text" under the "Scanned Document" section of the "Edit PDF" Menu.  My guess is that the OCR (optical character recognition) is reading in characters and then interpreting them.  Since my document was a poor scan, I can imagine that the mapping of my o, or your above 0 falsely generates the letter ü.  Not really a bug, just a function of how the scanning works, and in this case, its limitation.  Hope that helps.

Hi Gabrielg,

Sorry for the delay in response.

As per the issue description mentioned above, when editing a pdf, 0 is being written as u, is that correct?

Could you please share the version of Acrobat installed on the machine: Identify the product and its version for Acrobat and Reader DC

And, the operating system running on the machine-Mac/Windows?

Have you tried editing other pdfs? Does this behavior also seen when you type in other applications like MS Word/TextEdit?

Awaiting your response.

Shivam