@Kevin_Z 

Hi, thanks for the detailed reply, Kevin. 

I have a few questions:

- Why would the router broadcast CN as country code? 

- Even if CN was not working in macbook pro, it's clear that the router also broadcasts a different country for which MBP does show channels 36-48. So, it's not an issue of the laptop that the channels are not supported. MBP can technically support all channels, but automatically decides on the channels to use based on the region. FWIW, I'm running the latest MBP update and bought the laptop here in India from an official Apple authorized seller. Also, the region settings in my MBP is set to India. 

- Is there any other way for me to check whether I can force the router to display specific country code? 

- I've read several posts on apple forums and other websites where they have mentioned that it's the broadcaster's problem (i.e, router misconfigured with wrong code) since all the MBP does it pick up the strongest signal and use the country code broadcasted by it. 

--https://discussions.apple.com/thread/6665548

--https://www.howtogeek.com/211993/how-to-fix-conflicting-country-codes-and-improve-your-macs-wi-fi/

---the part where it says "When it wakes up, it scans for nearby Wi-Fi networks and the country code information tells the Mac which Wi-Fi settings it should use for this area. It appears that the Mac uses the country code from the first network it finds broadcasting this information.". This proves that the channels set on the MBP depend on the router's broadcast code.

--here is another discussion confirming the above claim: https://apple.stackexchange.com/questions/9768/change-mac-os-x-wireless-card-country-code

--another discussion: https://forums.macrumors.com/threads/my-macs-country-code-is-wrong-wifi-issues.1990925/ - "The country code is determined by the router that is used. ... The wifi channel, again, is determined by the router that you connect to. You would change the radio channel on your router. Your Mac cannot change the channel, you have to do that on the router, usually through the web access app that you use to change other settings on your router.".

-Essentially, if the wifi card is problematic, then I should never be able to pick up 5GHz bands at all, right? yet, why does it wary for each connection? and thus, the root of the inconsistent 5GHz connection.

-Finally, do you want me to perform any other additional tests that would give you some more information?

@ArcherC

I've yet to try any of the code modifying changes reported in some of the online forums. But I have tried setting all the locations correctly as some posts suggest.

In my tp-link router, I can only see channels 36 to 48 for 5GHz and the auto defaults to 36 (at least from what I have observed so far). But, I'm surprised there are no country settings like the one given in here: https://www.tp-link.com/us/support/faq/105/. So, naturally, if I set the channel to be 40 and if the MBP picks up the code as "CN", no 5GHz wifi will be displayed. Scan results will also return '0' 5GHz bands since in "CN" mode, only bands over 149 are "supported" by MBP. (Note: support in the sense, MBP decides that since it's in some specific region, that it's not supposed to connect to bands 36 to 48).

I still don't think it's the issue of the laptop since I am able to connect to 5GHz - just not consistently (i.e, when MBP picks up CN code from the router).

@Kevin_Z 

I understand the photos you have attached in your previous post. The only surprise I have is that bands 36-48 are also displayed for country code "CN", other than that, I do not have any other misunderstanding. 

>"while on the one hand, C7's country code is DE ONLY, no other different country code, so there is no conflicts;"

If so, why am I getting "CN" as country code sometimes? 

There have been many mentions in the links I've attached that the wifi card's model can't be country restricted in MBP. Just think about it, a laptop is meant to be carried everywhere and anywhere - what is the point of locking something in the hardware level - especially for wifi essentially restricting internet connectivity? So, because of this, I'm saying that MBP's hardware is not at fault here. Besides, you are ignoring my point that this issue happens only _sometimes_. If the problem was with conflicting country code in the MBP's hardware, this should happen _everytime_. 

Ok, leaving everything aside, why doesn't this model of the router have an option to specifically set the country code? 

The only option left for me to try is to flash openwrt or some sort of OSS and try to force the router to broadcast only EU region.

Use the MAC's built in WIFI scan tool so you can see the country code before you connect to the router. Power cycle the router, with WIFI on, press and hold the option key and click the WIFI symbol in upper right hand corner, click 'open wire diagnostics', do not click 'continue', instead click 'window' in upper left and in the drop down, click 'Scan', you will get a list of all of the WIFI channels and at the far right it will list country code.  

If it shows wrong counrty code before you connect, then it would appear not to be the MAC.

@pkz78 

Hi

I don't know if this is your problem, or whether you have already solved it, but I had similar issues with my old MacBook (2008), and came across this on the Deco page;

https://community.tp-link.com/en/home/forum/topic/200398

Good luck!

@petereh Hey! thanks for the tip! I'll check it out!