@Crosshairs 

Are you trying to connect both extender to the Wi-Fi router, how about the LEDs on TL-WA850RE after set up? 

If you want to use two range extenders, we recommended connecting both range extenders directly to the router , not extender wirelessly connects to another extender ( for the performance and stability of the 2nd extender)  Recommended Topology 1: RE1 )))(( Router )))(( RE2

If the Signal LEDs or Wi-Fi LEDs are Not on, you could do some troubleshooting mentioned in this thread:

Has connected to TP-Link extender but no internet, what can I do?