Swarm coordinator has failed to respond

Hey all, I can’t get my second computer to connect to a swarm coordinated by my first computer.

Swarm coordinator:
RAYVENGER
Windows 8.1
192.168.1.8

Swarm coordinator app sees RAYVENGER, does not see any other machines

Second computer:
OLDNBUSTED
Windows 7
192.168.1.5
Able to ping 192.168.1.8

Firewall is disabled on both computers, also they’re hardwired to the same gigabit ethernet router

Seeing this error output on OLDNBUSTED when I run “Ping Coordinator”:

9:06:02 PM: [Network] Pinging Coordinator...
9:06:02 PM: [PingRemoteHost] Successfully pinged RAYVENGER with RAYVENGER
9:06:02 PM: [Ping] Communication with the coordinator failed, job distribution will be disabled until the connection is established
9:06:02 PM: Exception details: System.NullReferenceException: Object reference not set to an instance of an object.
   at SwarmCommonUtils.NetworkUtils.<>c__DisplayClass1.<GetBestInterface>b__0(NetworkInterface Interface) in d:\BuildFarm\buildmachine_++depot+UE4-Releases+4.8\Engine\Source\Programs\UnrealSwarm\SwarmCommonUtils\Utils.cs:line 33
   at System.Linq.Enumerable.WhereArrayIterator`1.MoveNext()
   at System.Linq.Enumerable.Count[TSource](IEnumerable`1 source)
   at SwarmCommonUtils.NetworkUtils.GetBestInterface(IPAddress Address) in d:\BuildFarm\buildmachine_++depot+UE4-Releases+4.8\Engine\Source\Programs\UnrealSwarm\SwarmCommonUtils\Utils.cs:line 36
   at Agent.Agent.PingCoordinator(Boolean ForcePing) in d:\BuildFarm\buildmachine_++depot+UE4-Releases+4.8\Engine\Source\Programs\UnrealSwarm\Agent\Connections.cs:line 2121
9:06:02 PM: [Network]     Coordinator has failed to respond
9:06:02 PM: [Network] Coordinator ping complete

When I try to ping with the swarm coordinator set to 192.168.1.8:

9:06:57 PM: [PingCoordinator] Determined that we shouldn't ping the coordinator right now
9:06:58 PM:  ......... using SwarmCoordinator on 192.168.1.8
9:06:58 PM: [PingRemoteHost] Successfully pinged 192.168.1.8 with 192.168.1.8
9:06:58 PM: [Ping] Communication with the coordinator failed, job distribution will be disabled until the connection is established
9:06:58 PM: Exception details: System.NullReferenceException: Object reference not set to an instance of an object.
   at SwarmCommonUtils.NetworkUtils.<>c__DisplayClass1.<GetBestInterface>b__0(NetworkInterface Interface) in d:\BuildFarm\buildmachine_++depot+UE4-Releases+4.8\Engine\Source\Programs\UnrealSwarm\SwarmCommonUtils\Utils.cs:line 33
   at System.Linq.Enumerable.WhereArrayIterator`1.MoveNext()
   at System.Linq.Enumerable.Count[TSource](IEnumerable`1 source)
   at SwarmCommonUtils.NetworkUtils.GetBestInterface(IPAddress Address) in d:\BuildFarm\buildmachine_++depot+UE4-Releases+4.8\Engine\Source\Programs\UnrealSwarm\SwarmCommonUtils\Utils.cs:line 36
   at Agent.Agent.PingCoordinator(Boolean ForcePing) in d:\BuildFarm\buildmachine_++depot+UE4-Releases+4.8\Engine\Source\Programs\UnrealSwarm\Agent\Connections.cs:line 2121
9:06:58 PM:  ......... SwarmCoordinator failed to be initialized
9:06:58 PM: [PingCoordinator] Determined that we shouldn't ping the coordinator right now
9:06:58 PM: [PingCoordinator] Determined that we shouldn't ping the coordinator right now
9:06:59 PM: [PingCoordinator] Determined that we shouldn't ping the coordinator right now
9:06:59 PM: [Network] Pinging Coordinator...
9:06:59 PM: [PingRemoteHost] Successfully pinged 192.168.1.8 with 192.168.1.8
9:06:59 PM: [PingCoordinator] Determined that we shouldn't ping the coordinator right now
9:06:59 PM: [Ping] Communication with the coordinator failed, job distribution will be disabled until the connection is established
9:06:59 PM: Exception details: System.NullReferenceException: Object reference not set to an instance of an object.
   at SwarmCommonUtils.NetworkUtils.<>c__DisplayClass1.<GetBestInterface>b__0(NetworkInterface Interface) in d:\BuildFarm\buildmachine_++depot+UE4-Releases+4.8\Engine\Source\Programs\UnrealSwarm\SwarmCommonUtils\Utils.cs:line 33
   at System.Linq.Enumerable.WhereArrayIterator`1.MoveNext()
   at System.Linq.Enumerable.Count[TSource](IEnumerable`1 source)
   at SwarmCommonUtils.NetworkUtils.GetBestInterface(IPAddress Address) in d:\BuildFarm\buildmachine_++depot+UE4-Releases+4.8\Engine\Source\Programs\UnrealSwarm\SwarmCommonUtils\Utils.cs:line 36
   at Agent.Agent.PingCoordinator(Boolean ForcePing) in d:\BuildFarm\buildmachine_++depot+UE4-Releases+4.8\Engine\Source\Programs\UnrealSwarm\Agent\Connections.cs:line 2121
9:06:59 PM: [Network]     Coordinator has failed to respond
9:06:59 PM: [Network] Coordinator ping complete

Anyone have any ideas what might be going wrong?

Thanks

Good news, everyone!

OLDNBUSTED just had an old and busted version of .NET installed. One round of Windows Updates and everything was resolved!!