What does Windows say? Is there a message from Windows 10? Normally Windows asks for Admin privileges to install the PDF24 Creator and this is normally OK. Windows normally asks you whether you want to install the PDF24 Creator from the Geek Software GmbH as long as the signature of the installer is correct. Did you download from our http://www.pdf24.org pages? If not, we can not guarantee, that what you have downloaded is really the PDF24 Creator.
Ok, the PDF24 Creator uses a Windows Service to redirect print jobs. You can find the service in the Windows Service manager. The name is PDF24. This service must be in a running state in order to get the PDF printer to work. Did you stop the service or do you see some system errors in the Windows event viewer? If the PDF24 service is not running, then the PDF printer will not work. Normally the PDF24 pops up a message box that tells you, that the service is stopped and there is a button to restart it. This is implemented in the current version 8.4.1.
Thanks for the reply. I have checked in Windows Services and it has stopped. I did not get an error message. I have restarted it and it appears to work. I will know where to o if it happens again. Cheers