Hello,
you can switch off both separately.
Autostart: When you sign in to Windows, PDF24 starts its background process (pdf24.exe). This process receives the print jobs of the PDF printer and shows the tray icon. The autostart entry is not required. To disable it:
- Open the Task Manager (Ctrl+Shift+Esc).
- Open the page "Startup apps" (Windows 10: tab "Startup").
- Right-click the "PDF24" entry and select "Disable".
Please do not delete the entry from the registry instead, because every update creates it again. Details are in the manual: https://creator.pdf24.org/manual/11/#132-how-to-stopremove-the-pdf24-autostart-entry
PDF printer: Since version 11.31.0, the PDF printer is an optional component of the installer. Download the current version from https://tools.pdf24.org/en/creator, run the installer and deselect "PDF Printer" (and "Fax Printer", if it is selected) in the list of components. The other tools of PDF24 Creator keep working without the printer.