Heel erg bedankt @TAVL! I have placed an order for the cable and will be able to test it tomorrow.  

You are welcome. Please let us know if it works and if there is anything we can help you with.

Enjoy the weekend.

Hi @TAVL . Hope your weekend is going well so far. The new cable did not solve the problem. The router is not connecting to the internet via this cable. I have noticed that the RJ-45 cable that came with the router has 8 copper lines on on the plugs, while the RJ45/RJ11 cable only has 4. I suspect that this might be the problem. Any ideas?

@Jacques77

It's better to connect the router to a LAN port of your T-Mobile modem using an internet cable.

Make sure the LAN IP of both the modem and router is not the same (change LAN IP of one if needed).

DSL does not use 8 lines, but only 4. What does the router show? How does your socket look like? Is that the point of entry for the line into your home? You may show pictures, but please do not show personal data like the router data on the back.

Weekend is going great. A little bit too much rain and wind. Hope you are having a great weekend thus far. Besides the internet though.

From what I can gather from the Linksys support people is that I can connect my new router to my Zyxel router that I got from T-mobile. Am I correct in saying that I need to set the Zyxel modem to brigde mode? 

@Jacques77 

Yes you can connect it to the Zyxel using an internet cable.

Bridge mode is not an option on the Zyxel.

You can add you router in the DMZ of your Zyxel.

Make sure your router received a static IP from the Zyxel and then put your router in the DMZ of your Zyxel.

Log in on the web interface of the zyxel go the menu, netwerkinstellingen, thuis netwerk, NAT, DMZ and add the IP given to the Linksys.

DMZ will forward all internet traffic to your Linksys.

Thank you @Waqqas. I have never heard of DMZ before. Can you help me understand what DMZ means, and if my connection will still be as 1) good 2) fast 3) safe as it would be on the standard mode?

@Jacques77

Your connection will still be good fast and secure because the Linksys is behind the Zyxel firewall.

You are basically opening all ports to the Linksys.