diff --git a/.github/nativefuncs.json b/.github/nativefuncs.json
index 6f46095fd..13a7edd3d 100644
--- a/.github/nativefuncs.json
+++ b/.github/nativefuncs.json
@@ -729,6 +729,12 @@
 			"helpText":"",
 			"returnTypeString":"void",
 			"argTypes":"struct presence"
+		},
+		{
+			"name":"NSGetMasterServerAuthResult",
+			"helpText":"",
+			"returnTypeString":"MasterServerAuthResult",
+			"argTypes":""
 		}
 	]
 }
\ No newline at end of file
diff --git a/Northstar.Client/mod.json b/Northstar.Client/mod.json
index 7d695a4b7..f7c7c9b5b 100644
--- a/Northstar.Client/mod.json
+++ b/Northstar.Client/mod.json
@@ -128,6 +128,13 @@
     	{
 			"Path": "ui/ui_mouse_capture.nut",
 			"RunOn": "UI"
+		},
+		{
+			"Path": "ui/atlas_auth.nut",
+			"RunOn": "UI",
+			"UICallback": {
+				"After": "AtlasAuthDialog"
+			}
 		}
 	],
 	"Localisation": [
diff --git a/Northstar.Client/mod/resource/northstar_client_localisation_english.txt b/Northstar.Client/mod/resource/northstar_client_localisation_english.txt
index 8c7bab3a7..49e9ee43d 100644
--- a/Northstar.Client/mod/resource/northstar_client_localisation_english.txt
+++ b/Northstar.Client/mod/resource/northstar_client_localisation_english.txt
@@ -322,6 +322,11 @@ Press Yes if you agree to this. This choice can be changed in the mods menu at a
 		"INVALID_MASTERSERVER_TOKEN" 	"Invalid or expired masterserver token"
 		"JSON_PARSE_ERROR" 				"Error parsing json response"
 		"UNSUPPORTED_VERSION" 			"The version you are using is no longer supported"
+
+		"AUTHENTICATION_FAILED_HEADER"		"Authentication Failed"
+		"AUTHENTICATION_FAILED_BODY"		"Failed to authenticate with Atlas!"
+		"AUTHENTICATION_FAILED_ERROR_CODE"	"Error code: ^DB6F2C00%s1^"
+		"AUTHENTICATION_FAILED_HELP"		"Help"
 		
 		// Mod Settings
 		"MOD_SETTINGS"					"Mod Settings"
diff --git a/Northstar.Client/mod/scripts/vscripts/cl_northstar_client_init.nut b/Northstar.Client/mod/scripts/vscripts/cl_northstar_client_init.nut
index 2a2ed3dbe..a844478a2 100644
--- a/Northstar.Client/mod/scripts/vscripts/cl_northstar_client_init.nut
+++ b/Northstar.Client/mod/scripts/vscripts/cl_northstar_client_init.nut
@@ -41,3 +41,10 @@ global struct ServerInfo
     string region
     array< RequiredModInfo > requiredMods
 }
+
+global struct MasterServerAuthResult
+{
+    bool success
+    string errorCode
+    string errorMessage
+}
diff --git a/Northstar.Client/mod/scripts/vscripts/ui/atlas_auth.nut b/Northstar.Client/mod/scripts/vscripts/ui/atlas_auth.nut
new file mode 100644
index 000000000..89b7f7196
--- /dev/null
+++ b/Northstar.Client/mod/scripts/vscripts/ui/atlas_auth.nut
@@ -0,0 +1,56 @@
+global function AtlasAuthDialog
+
+void function AtlasAuthDialog()
+{
+	thread AtlasAuthDialog_Threaded()
+}
+
+void function AtlasAuthDialog_Threaded()
+{
+	// wait at least 1 frame so that the main menu can be loaded first
+	WaitFrame()
+
+	while ( !NSIsMasterServerAuthenticated() || GetConVarBool( "ns_auth_allow_insecure" ) )
+		WaitFrame()
+
+	if ( GetConVarBool( "ns_auth_allow_insecure" ) )
+		return
+
+	MasterServerAuthResult res = NSGetMasterServerAuthResult()
+
+	// do nothing on successful authentication
+	if ( res.success )
+	    return
+
+	EmitUISound( "blackmarket_purchase_fail" )
+
+	DialogData dialogData
+	dialogData.image = $"ui/menu/common/dialog_error"
+	dialogData.header = Localize( "#AUTHENTICATION_FAILED_HEADER" )
+
+	// if we got a special error message from Atlas, display it
+	if ( res.errorMessage != "" )
+		dialogData.message = res.errorMessage
+	else
+		dialogData.message = Localize( "#AUTHENTICATION_FAILED_BODY" )
+
+	if ( res.errorCode != "" )
+		dialogData.message += format( "\n\n%s", Localize( "#AUTHENTICATION_FAILED_ERROR_CODE", res.errorCode ) )
+
+	string link = "https://r2northstar.gitbook.io/r2northstar-wiki/installing-northstar/troubleshooting"
+	// link to generic troubleshooting page if we don't have an error code from Atlas
+	if ( res.errorCode != "" )
+		link = format( "%s#%s", link, res.errorCode )
+
+	CloseAllDialogs()
+	AddDialogButton( dialogData, "#OK" )
+	AddDialogButton( dialogData, Localize( "#AUTHENTICATION_FAILED_HELP" ), void function() : ( dialogData, link )
+	{
+		// todo: get MS to redirect, so i can use an MS link or something?
+		LaunchExternalWebBrowser( link, WEBBROWSER_FLAG_FORCEEXTERNAL )
+		// keep the dialog open
+		OpenDialog( dialogData )
+	} )
+
+	OpenDialog( dialogData )
+}