scanworks 3.1 unsupported file content

[ETS5]

I have a PDF that scanworks says unsupported file content yet the PC will open the PDF. We are using Scanworks 3.1

[shadowsports]

Greetings,

Is Scanworks a Canon product?  I don't see any listing for it when searching.  

[ETS5]

Rick,

I thought it was provided with the Canon scanner/printer, but it is not. It's a software package from Colortrack.

Thank you - Scott