I can confirm that the problem exists. Today, Port #1 also stopped working on my XE75 for no apparent reason (no power outages, etc.). It shows a link on the port, but there is no data exchange. My Deco's WAN connection type is DHCP, and it couldn't obtain an address from the router. I also tried switching to Static IP, but there was still no data exchange between the router and the Deco unit. 

When I reconnected the cable from the router to Port #2, the LED on the Deco immediately turned green, and it successfully obtained an IP address. I then tried upgrading the firmware to the latest version - 1.3.2 Build 20240119 Rel. 39178. The upgrade was successful, but it didn't resolve the issue with Port #1. It's still "dead" (no data exchange, unable to obtain an IP address through DHCP, etc.). 

So, it seems like a common problem. My Deco revision is EU/1.0.

  @AGMV Same problem here on to XE75's 

  @DeckerSU Yes, I have the same firmware on an XE75 (EU/1.0) in AP mode.  Power had been off, and when it was restored it had a solid red light - IP was not obtained, defaulting to 192.168.68.1.  After some struggling including a full reset, I came to find that port 1 didn't work, despite it showing as a link up @ 1Gbps on the switch. Switched it to port 3, closest to the power plug, and it worked right away. Frustrating, especially as it is outside the warranty period now. Pretty poor if it is actually a hardware issue rather than firmware, given it isn't a cheap bit of kit.

  @AGMV Same problem here with hardware version EU/V1 and firmware version 1.3.2 BUILD 20240119. Port 1 of the main DECO XE75 unit suddenly stopped working, this setup worked for nearly one year without issues. A hard reset of the main unit did not solve the problem and during the night ip address was assigned to my Tado Gateway which is conected to the main deco pod on port 1. Devices which were connected to port 2 and 3 seems not affeted and funtion properly. Now it works again it seems not hardware related but firmware related. There are so less debugging options in this device so its not possible to pinpoint the exact problem. TP-LINK support please help!!!
 

  @AGMV At this point a recall/extended warranty is needed for XE75. TP-Link please address this issue!

My port 1 has been dead for more than 6 months now! And I always thought it was my Mac's problem. I can't believe this post existed for so long.

At this point most of us are reaching the end of warranty. I'm starting a RMA process but who knows when the replacement unit will fail.

TP-Link should either recall all these failing units, or extend the warranty of all XE75, as this PORT 1 NOT WORKING ISSUE is such a widely seen problem.

  @LJXXXD I bought the 3 pack in December 23 and in the last 2 weeks in all three xe75 the first port died. 
I called the support and they told me, after several tests, that I must change everything. 
I

am

not

happy

Same.  Two XE75s with port one not working on either.

  @AGMV 

Very frustrating issue.  I am posting merely to log the issue.  I have a large network with many switches involved (all TP-Link equipemnt).  I too got connection without IP address distribution.  Didn't realize it was port 1 but that sounds currect.  After a lot of playing and effectively using ports from switches and Deco units, I was able to get everything to work again.  (2) of my 3 XE5300's were affected (i.e. no LAN port 1).

  Same issue here. after 7 months of no problem port 1 just died on my main deco ( have 2 units hardhaul connected)

  @AGMV 

Posting about the same issue. Today my XE75 main unit's Top port stopped working. Can not be used for anything anymore. No ethernet backhaul, no WAN, nothing.

Really frustrated about this, since I bought the unit recently, and even if I get a warranty unit, I suppose the issue will come back later on.