Following the below steps;
1、Make your windows pc connect to your printer’s hotspot via wifi.
2、Open the 192.168.12.1 on your browser.
4、Wait for a few seconds until the black windows shut down
5、Refresh the page
Note: Sorry, that file type is not permitted to upload for security reasons, so a link attached, if you can’t get the files, plz contact our support. And it only applies to firmware versions below 3.14, and all OL printer firmware is 4.2.