@nu1mlock

Sure thing, you can't buy it anymore but it's a Huawei E5172.

The CG NAT sounds plausible, but if that's the case why did the MR400 work fine for months up until the beginning of December?

From what I gather the MR400 should work if we can enable ipv6-tunnelling, however my router claims no WAN-connection is available when I try to set it up with these settings: http://as1257.tele2.net/ipv6/6rd.php

Can anyone else get this to work?

@JensPalmqvist 

Well, I don't know about you of course, but I can assure you that I've had the same issue with port forwarding and a different IP on whatsmyip than in the router for as long as I've had Tele2 Unlimited, which is almost two years now.

My router (MR400) has never gotten a Public IP - NEVER during the last almost two years.

The MR400 stopped working properly with Tele2's 4G in December, but to my knowledge it never had a Public IP. I've always had the same issues with the MR400, like port forwarding not working, same goes for DMZ of course. Basically no NAT features made any difference and haven't during the whole time I've had this MR400 router.

I know for a fact that I am dealing with a CG NAT, there's no doubt about it. I am assuming everyone else with Tele2 Unlimited are too, as well as everyone else using this router and Tele2 in Sweden.

@nu1mlock

Fair enough, but then what suddenly killed services like YouTube/Netflix etc.?

@JensPalmqvist 

I don't know. But what I do know is that they did work for almost two years with a Private IP from Tele2. Since we all seems to have started to get the issue at around the same time it is possible that Tele2 has changed something that we have no information about.

After all, it seems like our SIMs works in all other routers and phones, so there's something specific to Tele2 and the MR400. Point being that the MR400 is faulty since everything works in all other routers.

Okay, so I contacted the Tele2 support now and according to them you need to use a router/modem provided from them to not get stuck behind their NAT. My backup router is a model they stocked before, so that's probably why I get a public IP on that.

There is no "workaround" for this and he was unaware of any changes in the service during the last year or so, so he couldn't say why it suddenly stopepd working in december.

He had no information about ipv6-tunnelling as that's not officially supported, but can you guys try to set it up so we know if it's only my router that can't get it to work? Here's the link again: IPV6-tunnelling

@JensPalmqvist 

I tried setting up IPv6 tunnel as per their instructions, but I also get an error:

Error code: 86257
No available WAN connection detected. Please make sure that you select the correct tunneling mechanism and try again. If the problem still exists, please contact your ISP.

I have ordered a B525 directly from Tele2. I've given up on the MR400. I'll be returning the RUT240 and use the B525 instead. That way I can get a public IP and actually use port forwarding etc. while also being able to lock the router to specific bands. As I've tried this yesterday I got about 10Mbit/s extra by locking to another band, which isn't possible with the MR400.

@Kevin_Z 

Well? It seems that not only MR400 has these issues, but also MR200 and MR6400. All routers have the same issue and you have been unable to solve this for A WHOLE MONTH! 

While there have been holidays, this is widespread enough that it needs immediate attention and TP-Link has been unable to give any kind of help.

This warrants a full recall of all MR200, MR400 and MR6400 since you have been unable to provide us with a working firmware update.

This requires an immediate reply.

@Kevin_Z well? It's been a month a our MR400 are still unusable!