Interface not supported

Hello to all, one of my customer has following problem: after installation of our product (using PDF Creator via COM) onto five computers - one of them works correctly meanwhile four else do not work and an error message "Interface not supported" is generated while creating an PDFCreator instance. Do anybody know what could it caused by ? Are there any necessary settings on the destination computer ? Using PDFcreator as a pritre for example in MS Word is OK.


Thank you for any advice.