Open any TWAIN-compatible software (e.g., with TWAIN plugin, GIMP with TWAIN plugin, or Paint.NET with TWAIN add-on):

If you don’t have the CD, get the XP driver from a legacy driver archive (e.g., DriverGuide, Umax scanner archive). The filename is often UmaxAstra4100_XP.exe .

Select > Let me pick from a list of available drivers . Choose Imaging devices from the list.

Do you have the or a downloaded setup file ready to use for the compatibility mode steps? How to use OLD scanner without driver in windows