What is the issue?
There is a formal error in the date value in the metadata of the PDF.
Note: This error message is displayed by PAC versions starting from 24.0.
Why does this error occur?
One possible reason is that the PDF was created with axesWord version 23.1.x.x (it is a known bug).
How to fix it?
Possibility 1:
Install axesWord version 23.2.0.0 and create PDF again.
You can download current axesWord version from our download site.
Possibility 2:
Open the PDF with Acrobat and save it again. This fixes the issue.