@yo1 "What if you connect the Provider cable to the PC directly, will you negotiate 1000Mbps?" I'm still limited to 100Mbps, even if I change adapter duplex to 1000Mbps. This is the problem. It seems...

@SaintCedd Sorry, the screenshots seem not upload successfully, can you please send it again?

@tpta C80 supports NAT Loopback (hairpinning) by default. May I know who is your ISP? Is it possible to configure the W9960 into bridge mode, then configure the internet settings on the C80 to...

@SARAVA-99 If you don't remember the wireless network name and password, refer to this instruction to find it: https://www.tp-link.com/support/faq/399/

@yo1 What if you connect the Provider cable to the PC directly, will you negotiate 1000Mbps? Please show us the screenshot if it is. If the modem negotiates fine when connected to the PC directly,...

@Thomas-daison What is the firmware of the WR845N? Ensure it is up-to-date: https://www.tp-link.com/support/download/tl-wr845n/#Firmware