Excel 2016 issues

Hello all,

Read a few similar posts on here and tried all the suggestions regarding HKCR PrintTo string, but nothing works and at least a couple of years old, so I thought I'd try again with this issue.

Windows 10 1909, PDF Creator 4.0.3, Office 2016 64-bit

All functions of PDF Creator work correctly for Word and PowerPoint, but the only way to convert Excel files is to open the document and print to the PDFCreator printer. File Explorer context menu option and browing to a document from within PDF Creator itself, just launches Excel but without opening the document and it just sits there - nothing else happens. Same with .xls and .xlsx file types.

Tried downgrading to PDF Creator 3.4.0 and it's no different. Any ideas??