Unknown device appears in the printer installed in win8 system. The forced installation prompts that the digital signature cannot pass. How to forcibly turn off digital signature?

Move the mouse to the upper right corner to drop down or the lower right corner to raise the setting.

Then select more computer settings.

Jump to the settings page, select General, select Advanced Start on the right, and restart immediately.

After restarting, the following will appear. Select Troubleshooting.

After selecting, select, advanced options?

Then select windows startup settings.

After restarting, just select "Disable driver forced signature" in the advanced menu.

Then select Disable driver forced signing.

Then you can happily install the driver after entering the desktop.

PS: use Tab, arrow keys (up, down, left and right) and Enter to confirm the operation.