Good sharing! Thanks!

Great news !:D

You may have a try like this: Attempt to set the printer to online. Go to "Settings" and then " Printers." Right-click on the printer and select "Use Printer Online.

Normally the NAT boost won't affect the Lan speed. Try to restart the router and Lan clients after NAT boost enabled. If the issue still exist, contact TP-Link Support at support@tp-link.com for help.

What is the operation mode of TL-WR843N? Perhaps the Lan IP was conflict with the WAN IP , so it changed itself. How about changing the Lan IP to something else?

Good sharing!