Signing existing pdf file

Hello guys,

 

I'm exploring PDFCreator 1.02 and have trouble with signing existing pdf file with certificate. I tested with Word.doc and signing is OK. But I am not allowed to open pdf file with Print monitor. Seems only .ps files may be opened. What I'm doing wrong?

I did read http://www.pdfforge.org/content/signing part, but it did not help much.

 

Thank you

 

Sapnai