To create a custom page size in Windows 11:
1. Search for "Printers & scanners" from the Windows 11 "Search" menu. Scroll down to "Related settings" and then click on "Print Server Properties".
2. In the "Print Server Properties" window, name and set the paper size dimensions.
3. Select "Save Form" and close the window. Your form should now be available to Win2PDF. Here is a short video showing how to create and use this custom paper size.
How to create a custom paper size with Windows 7