@danico 

Hi Dan, from the log error, the RE450 failed to scan the main router's wifi, that is why it failed to connect to the main router. 

Try to customize the wireless settings of the main router first, including the wireless channel, for 2.4GHz, use channel 1, 6 and 11, and use channel 36, 40 and 44 for the 5GHz. 

After that you can reconfigure it as the instruction below: 

https://www.tp-link.com/support/download/re450/#video 

https://www.tp-link.com/support/faq/1400/

Note: This time, please login to the web UI of the RE450 to set it up. 

May it help. 

@danico 

In my opinion, the wireless channel can be customized; have you ever tried to change another wireless channel of 2.4GHz and 5GHz? 

Can RE450 detect other wireless networks? If it can, then it won't be a defective unit. Instead, to make it work, try to adjust the wifi settings of the main router to give it a go.

Best regards. 

@danico 

I can get your point, while cause the repeater cannot detect the SSID with channel 13, you can give it a go by changing the wireless channel to 1 or 6/11 to verify whether it can be detected.

If it works with other channels, then we can make the range extender work at first, and then we can record this case and forward it to our product department. 

May it help.