The specific problem our group and others were experiencing (NNThink 2, servers suddenly stopped allowing connections through server browser) now appears to have been resolved as of a day or two ago. Other people may still be experiencing issues, but for our group at least that problem is gone and everyone can connect normally again through the server browser or by any other means. We didn't need to make any setup changes on clients or on the server. We're running a modded version of ARMA 2 (ACE and lots of islands).

Make sure your Day Z preset is selected on the left. Then right-click the server you want under "Server Browser", go to the "Updater Actions" sub-menu, then select "Join the server". It is possible to filter by name and other parameters by using the boxes over the various columns. To search for servers with "UK" in them, filter by "%UK" in the box above name for example.

"Connecting failed" can happen for a lot of reasons, which doesn't help. But a lot of people and servers are having "Connecting failed" issues accompanied by NAT and NNThink errors in their log file, which is what started happening last evening. Check your .rpt log file to be sure (see earlier in this thread for where it's located).

Just to double-check, what does your .rpt file say when you try to join using the Six Updater? Make sure to use the Six Updater not the Six Launcher; have no idea whether the Six Launcher will work at all.

Hrm, that's annoying. We tested it on one public server and one private server (hosted on someone's machine) running ARMA 2 Operation Arrowhead with mods.

A temporary solution which works for clients. Quoting my friend again: You CAN join servers that you get Connecting Failed to by using the Six Updater. You can join servers through the Six Updater's built-in server list. The Six Updater adds the command line parameters " -connect=<the Server IP here> -port=2302".

A temporary solution which works. Quoting my friend again: You CAN join servers that you get Connecting Failed to by using the Six Updater. The Six Updater adds the command line parameters " -connect=<the Server IP here> -port=2302".

Posted this on the other topics, but may as well put it here as well: A friend did some research: "On the servers where I can connect, Arma immediately tries to connect to port 2302 Whereas the games where it doesn't work, ArmA tries to negotiate the UDP using 69.10.30.x IPs - I'm guessing those are the negotiation servers. (And they answer with ICMP Destination unreachable) IGN owns Gamespy, right? The 69.10.30.x IPs resolve through IGN's dns servers. It could be that in case where the server is behind a NAT it'll do the negotiation." Doesn't help solve the problem at all, but at least gets us closer to figuring out what's going wrong.

A friend did some research: "On the servers where I can connect, Arma immediately tries to connect to port 2302. Whereas the games where it doesn't work, ArmA tries to negotiate the UDP using 69.10.30.x IPs - I'm guessing those are the negotiation servers. (And they answer with ICMP Destination unreachable) IGN owns Gamespy, right? The 69.10.30.x IPs resolve through IGN's dns servers. It could be that in case where the server is behind a NAT it'll do the negotiation."

As a further diagnostic guys, go to your logfile (it's named arma2oa.rpt) and report what error you find there. The logfile is in: C\Users\<your username>\AppData\Local\ArmA 2 OA\

Another thread on the official BI forums that appears to be on the same issue: http://forums.bistudio.com/showthread.php?136844-Can-no-longer-host-multiplayer-games-with-a-friend

That's the error message people are getting. NNThink is a Gamespy API, and the problem started for people either 8:30 or 9:30GMT yesterday. Originally thought it was a Gamepsy issue and it would pass, but woke up today and still having issues getting people to connect to my ARMA 2 server.

There's a thread on the Troubleshooting forums where a lot of users are reporting the same issue: http://dayzmod.com/f...ed/page__st__20 A few unrelated posts in there, but most people reporting the same symptoms/problem. The main error on clients connecting is, "NAT Negotiation failed (NNThink - result 2)" The server error being shown is, "NAT Negotiation failed - unable to communicate with the server" This is happening with modded ARMA 2 OA servers as well: http://forums.bistudio.com/showthread.php?135123-Dedicated-Server-NAT-Negotiation-Failed&p=2193217#post2193217

This is not just a Day Z issue, our group is having trouble with base ARMA 2 with mods. In the middle of a playing session our server suddenly stopped accepting new players connecting, and hasn't worked since. A few related threads: http://dayzmod.com/forum/index.php?/topic/41845-95208-connecting-failed/ - other people with the same problem http://dayzmod.com/forum/index.php?/topic/41828-server-suddenly-stopped-working/ - Day Z server hosts have their servers suddenly stop working http://forums.bistudio.com/showthread.php?135123-Dedicated-Server-NAT-Negotiation-Failed - same issue when running ARMA 2 Operation Arrowhead servers

If I'm reading the comment I think you mean, that is completely unrelated.