Hi@R23,

Thank you for reporting your issue to our community.

Please note that the RE605X doesn't support create Easymesh network via Ethernet backhaul with EX511. If you want the RE605X to access internet via Ethernet backhaul,you can consider to set it as an Access Point

For Tether App: How to configure Range Extender as an Access Point via Tether APP

For Web Management Interface: How to configure the range extender as an access point (new logo)

Wi-Fi signal strength can be considerably improved by repositioning the range extender. You could try the following particular solutions:
1. Mind the distance: the extender with the external antenna should be positioned between 25 and 40 feet away from the router, while the extender with the internal antenna should preferably be placed between 20 and 35 feet away. 
2. Raise the range extender: lift the range extender to approximately four-feet high to match the main router's height. The height will help the extender receive a better signal from the primary router and ensure that mobile devices receive a stronger signal from the extender.
3. Position the antennas vertically: most TP-Link range extenders have rotatable, adjustable antennas. Place the antenna vertically to the ground to guarantee the extender receives and transfers data as efficiently as possible. You can place the extender upside down but don't place it sideways. 
4. Avoid obstructions: Don't place the extension near objects that could reflect or absorb the signal, such as brick supports, mirrors, or big metal blocks. Furthermore, it is advised to steer clear of other distributed devices' radio frequency transmissions, as they are primary Wi-Fi interference. 
Please click this link for additional details and illustrations:  How to place your wireless Range Extender for optimal reception and performance

Hi@R23,

Thank you for your reply.

Here is the link:  EasyMesh Range Extenders Start Supporting Building a EasyMesh Network via Ethernet Backhaul

Please note, the EX511 is a customized device specifically designed for local Service Providers. Its software is tailored to meet the unique requirements of these providers, ensuring alignment with their specific needs. 

May I know what is the distance between EX511 and RE615X? It is recommended that you adjust the distance to 6-8m to avoid signal interference;
Please test the Wi-Fi signal of the main router at the same place as the RE615X. If it is also weak or not good, please change channel of router.
Avoid physical obstruction: Make sure there are no high attenuation obstacles such as metal objects and load-bearing walls between the two.
Did you try WPS method to create Mesh network? If you don't mind, please reset the range extender and reconfigure it.

Hi @R23,

Many thanks for your detailed reply.

Could you please check, if the guest network and multi-SSID are enabled on EX511? If yes, please turn them off. Then reset the RE605X and reconfigure it again.

Thank you.

Hi @R23,

We have reported the issue to the support engineers, they will likely reach out to you via email to continue to troubleshoot your issue. Please check your email box and confirm.