diff --git a/apps/openmw-mp/Networking.cpp b/apps/openmw-mp/Networking.cpp
index a2bda22ab..298e0010b 100644
--- a/apps/openmw-mp/Networking.cpp
+++ b/apps/openmw-mp/Networking.cpp
@@ -321,7 +321,7 @@ void Networking::newPlayer(RakNet::RakNetGUID guid)
         if (pl->first == guid) continue;
 
         // If an invalid key makes it into the Players map, ignore it
-        else if (pl->first == RakNet::UNASSIGNED_RAKNET_GUID) continue;
+        else if (pl->first == RakNet::UNASSIGNED_CRABNET_GUID) continue;
 
         // if player not fully connected
         else if (pl->second == nullptr) continue;
diff --git a/apps/openmw-mp/main.cpp b/apps/openmw-mp/main.cpp
index f9c490a08..1e69f6542 100644
--- a/apps/openmw-mp/main.cpp
+++ b/apps/openmw-mp/main.cpp
@@ -239,9 +239,9 @@ int main(int argc, char *argv[])
 
         switch (peer->Startup((unsigned) players, &sd, 1))
         {
-            case RakNet::RAKNET_STARTED:
+            case RakNet::CRABNET_STARTED:
                 break;
-            case RakNet::RAKNET_ALREADY_STARTED:
+            case RakNet::CRABNET_ALREADY_STARTED:
                 throw runtime_error("Already started");
             case RakNet::INVALID_SOCKET_DESCRIPTORS:
                 throw runtime_error("Incorrect port or address");
diff --git a/apps/openmw/mwmp/Networking.cpp b/apps/openmw/mwmp/Networking.cpp
index b5779cc21..646737482 100644
--- a/apps/openmw/mwmp/Networking.cpp
+++ b/apps/openmw/mwmp/Networking.cpp
@@ -200,7 +200,7 @@ Networking::Networking(): peer(RakNet::RakPeerInterface::GetInstance()), playerP
     RakNet::SocketDescriptor sd;
     sd.port=0;
     auto b = peer->Startup(1, &sd, 1);
-    RakAssert(b==RakNet::RAKNET_STARTED);
+    RakAssert(b==RakNet::CRABNET_STARTED);
 
     playerPacketController.SetStream(0, &bsOut);
     actorPacketController.SetStream(0, &bsOut);
@@ -303,6 +303,13 @@ void Networking::connect(const std::string &ip, unsigned short port, std::vector
                     queue = false;
                     break;
                 }
+                case ID_INCOMPATIBLE_PROTOCOL_VERSION:
+                {
+                    errmsg = "Network protocol mismatch!\nMake sure your client is really on the same version\n"
+                        "as the server you are trying to connect to.";
+                    queue = false;
+                    break;
+                }
                 case ID_CONNECTION_REQUEST_ACCEPTED:
                 {
                     serverAddr = packet->systemAddress;