To download the verified SPD Driver R420, follow these steps:

Includes a DPInst executable for one-click setup.

You have two options here:

If the driver is in a ZIP or RAR archive, right-click the file and select "Extract All..." or use a program like 7-Zip to extract the contents to a new folder. Remember where you saved this folder.

https://www.samsung.com/us/support/downloads/ → Search "NP-R420"