Airport Extreme DHCP and NAT

The company that distributes the signal throughout the building is the one I spoke to.

If this is an Ethernet connection, then there is another router at the building location that is providing that connection. If that's the case, then the AirPort Extreme needs to be setup in Bridge Mode. Technically, the setting is actually "Off (Bridge Mode)", which means that the DHCP and NAT routing services of the AirPort Extreme are turned "Off", because you already have another router in the building that is providing DHCP and NAT services.

Normally, you never want two routers both trying to provide DHCP and NAT services. That can create IP address conflicts and another condition known as Double NAT, which can cause any of a number of other issues.

Our setup is one with DHCP and NAT, where it used to just be a bridge. I have the network set up and it is reading the ISP signal properly.

Then, that would likely explain the problems that you are having. Even if you are not getting IP address conflicts from having two routers, the Double NAT can cause poor connections, no or slow connections, browsing issues (where some sites will load while others will not) and other unpredictable results.

The AirPort Extreme should be setup to operate in Bridge Mode, unless there is some unknown reason otherwise. Sometimes, you do have to try to run two routers, and sometimes you can get away with it......but in general it is always best to only use one router on a network, and setup the other router(s) in Bridge Mode.

Unfortunately, this is one of those Catch 22 types of situations.

The Apple AirPort routers.....in my experience.....just do not perform well at all when they are configured to use DHCP and NAT when there is already another router upstream on the network doing the same thing. There is a reason why Apple's AirPort Utility software tells you set up the AirPort in Bridge Mode when it detects another router also doing DHCP and NAT on the network.

Yes, other users may disagree and say that "it works for me". But, the fact that some users have been able to make this work.....does not really help in the situations where it simply does not work.

You really have three options......

1) Keep resetting the AirPort Extreme and hope that the settings will "stick" at some point. (I think you may already have some idea about your chances here)

2) Try a router from another manufacturer. Ask around and find out what is working for other users at your complex.

3) Contact other Internet Service Providers to check on the feasibility of having your own broadband Internet connection at your place.

Good luck......keep us advised your progress if you can.....as it will help other users in similar situations.

Answer to this config is to have Comcast/Xfinity put THEIR modem/router into Bridge mode w/their tech support. U then reboot everything & put 1st Apple extreme into DHCP/NAT config settings w/Apples tech support. Then if u have second extreme as I do u put 2nd extreme into Bidge mode also. So yes u want only one router to have DHCP/NAT configured but APPLES is the BEST! Bypass provider & configure 1 thru Apple. Works awesome!

Answer to this config is to have Comcast/Xfinity put THEIR modem/router into Bridge mode w/their tech support.

Not the answer in this case. You missed the part above about the Comcast modem/router providing Internet to all of the users in the apartment complex.

If you put the modem/router in Bridge Mode, only one user will be able to connect their router and get an Internet connection. All the other users at the apartment complex will not be able to connect to the Internet.