: Connect your programmer via USB. If the driver does not auto-install, manually point Windows to the usb driver folder within the Elrasoft directory (e.g., C:\Program Files\ELRASOFT\UPA-USB Suite\USB Driver ).
Elrasoft UpUSB Driver: How to Download & Update (2026 Guide)
The original official driver package can be found on the Wayback Machine.
After installing, you can turn test signing off: bcdedit /set testsigning off .