diff --git a/assets/js/components/Auth/auth.ts b/assets/js/components/Auth/auth.ts
index b23f64171..cc73cb0b5 100644
--- a/assets/js/components/Auth/auth.ts
+++ b/assets/js/components/Auth/auth.ts
@@ -108,7 +108,13 @@ function debounedUpdateAuthStatus() {
 }
 
 // update auth status on reconnect or server restart
-watch(() => store.state.offline, debounedUpdateAuthStatus);
-watch(() => store.state.startup, debounedUpdateAuthStatus);
+watch(
+  () => store.state.offline,
+  (offline) => offline && debounedUpdateAuthStatus()
+);
+watch(
+  () => store.state.startupCompleted,
+  (startupCompleted) => startupCompleted && debounedUpdateAuthStatus()
+);
 
 export default auth;
diff --git a/assets/js/components/Footer/OfflineIndicator.vue b/assets/js/components/Footer/OfflineIndicator.vue
index 1dcc92b4c..b334c2d82 100644
--- a/assets/js/components/Footer/OfflineIndicator.vue
+++ b/assets/js/components/Footer/OfflineIndicator.vue
@@ -1,6 +1,6 @@
 <template>
 	<div data-testid="offline-indicator" :aria-hidden="!visible">
-		<div v-if="offline" class="modal-backdrop" />
+		<div v-if="offline || starting" class="modal-backdrop" />
 		<div
 			class="fixed-bottom alert d-flex justify-content-center align-items-center mb-0 rounded-0 p-2"
 			:class="{ visible: visible, 'alert-danger': showError, 'alert-secondary': !showError }"
@@ -23,6 +23,14 @@
 				<CloudOffline class="m-2" />
 				{{ $t("offline.message") }}
 			</div>
+			<div v-else-if="starting" class="d-flex align-items-center">
+				<span
+					class="spinner-border spinner-border-sm m-1 me-2"
+					role="status"
+					aria-hidden="true"
+				></span>
+				{{ $t("offline.starting") }}
+			</div>
 			<div
 				v-else-if="showError"
 				class="d-flex align-items-center container px-4 justify-content-center"
@@ -67,6 +75,7 @@ export default defineComponent({
 	props: {
 		offline: Boolean,
 		fatal: { type: Array as PropType<FatalError[]>, default: () => [] },
+		startupCompleted: Boolean,
 	},
 	data() {
 		return { dismissed: false };
@@ -78,8 +87,17 @@ export default defineComponent({
 		restarting() {
 			return restart.restarting;
 		},
+		starting() {
+			return this.startupCompleted === false;
+		},
 		visible() {
-			return this.offline || this.restartNeeded || this.restarting || this.showError;
+			return (
+				this.starting ||
+				this.offline ||
+				this.restartNeeded ||
+				this.restarting ||
+				this.showError
+			);
 		},
 		showError() {
 			return (
@@ -115,16 +133,19 @@ export default defineComponent({
 .alert {
 	opacity: 0;
 	transform: translateY(100%);
+	min-height: 58px;
 	transition:
 		transform var(--evcc-transition-fast) ease-in,
 		opacity var(--evcc-transition-fast) ease-in;
-	min-height: 58px;
 	/* above backdrop, below modal https://getbootstrap.com/docs/5.3/layout/z-index/ */
 	z-index: 1054 !important;
 }
 .alert.visible {
 	opacity: 1;
 	transform: translateY(0);
+	transition:
+		transform var(--evcc-transition-medium) ease-in,
+		opacity var(--evcc-transition-medium) ease-in;
 }
 
 .fatal-icon {
diff --git a/assets/js/components/Site/Site.vue b/assets/js/components/Site/Site.vue
index 2be248e6e..15f4b3efa 100644
--- a/assets/js/components/Site/Site.vue
+++ b/assets/js/components/Site/Site.vue
@@ -6,7 +6,7 @@
 				data-testid="header"
 			>
 				<h1 class="d-block my-0">
-					<span v-if="!isInitialSetup">
+					<span v-if="!setupRequired">
 						{{ siteTitle || "evcc" }}
 					</span>
 				</h1>
@@ -20,17 +20,25 @@
 				</div>
 			</div>
 			<HemsWarning :circuits="circuits" />
-			<Energyflow v-if="loadpoints.length > 0" v-bind="energyflow" />
+			<Energyflow v-if="!setupRequired" v-bind="energyflow" />
 		</div>
 		<div class="d-flex flex-column justify-content-between content-area">
 			<div
 				v-if="hasFatalError"
 				class="flex-grow-1 align-items-center d-flex justify-content-center"
 			>
-				<h1 class="mb-5 text-gray fs-4">{{ $t("startupError.title") }}</h1>
+				<div class="d-flex flex-column align-items-center mb-5 gap-4 mx-4 text-center">
+					<h1 class="text-gray fs-4 my-0">{{ $t("startupError.title") }}</h1>
+					<p v-for="fatalText in fatalTexts" :key="fatalText" class="text-break my-0">
+						{{ fatalText }}
+					</p>
+					<router-link class="btn btn-secondary" to="/config">
+						{{ $t("startupError.editConfiguration") }}
+					</router-link>
+				</div>
 			</div>
 			<div
-				v-else-if="isInitialSetup"
+				v-else-if="setupRequired"
 				class="flex-grow-1 d-flex align-items-center justify-content-center p-3"
 			>
 				<div
@@ -118,6 +126,7 @@ export default defineComponent({
 
 		notifications: { type: Array as PropType<Notification[]>, default: () => [] },
 		offline: Boolean,
+		setupRequired: Boolean,
 
 		// details
 		gridConfigured: Boolean,
@@ -199,9 +208,6 @@ export default defineComponent({
 			// work in progess
 			return false;
 		},
-		isInitialSetup() {
-			return this.loadpoints.length === 0;
-		},
 		footer() {
 			return {
 				version: {
@@ -226,6 +232,11 @@ export default defineComponent({
 		hasFatalError() {
 			return this.fatal.length > 0;
 		},
+		fatalTexts() {
+			return this.fatal.map(({ error, class: errorClass }) =>
+				errorClass ? `${errorClass}: ${error}` : error
+			);
+		},
 	},
 	methods: {
 		selectedLoadpointChanged(id: string | undefined) {
diff --git a/assets/js/types/evcc.ts b/assets/js/types/evcc.ts
index 09db0834d..db5b1b047 100644
--- a/assets/js/types/evcc.ts
+++ b/assets/js/types/evcc.ts
@@ -50,7 +50,8 @@ export interface FatalError {
 
 export interface State {
   offline: boolean;
-  startup?: boolean;
+  setupRequired?: boolean;
+  startupCompleted?: boolean;
   loadpoints: Loadpoint[];
   forecast: Forecast;
   currency?: CURRENCY;
diff --git a/assets/js/views/App.vue b/assets/js/views/App.vue
index db614c1c8..fc124a33d 100644
--- a/assets/js/views/App.vue
+++ b/assets/js/views/App.vue
@@ -1,6 +1,10 @@
 <template>
 	<div class="app">
-		<router-view :notifications="notifications" :offline="offline"></router-view>
+		<router-view
+			v-if="showRoutes"
+			:notifications="notifications"
+			:offline="offline"
+		></router-view>
 
 		<GlobalSettingsModal v-bind="globalSettingsProps" />
 		<BatterySettingsModal v-if="batteryModalAvailabe" v-bind="batterySettingsProps" />
@@ -67,6 +71,9 @@ export default defineComponent({
 		batteryModalAvailabe() {
 			return store.state.battery?.length;
 		},
+		showRoutes() {
+			return this.state.startupCompleted;
+		},
 		state() {
 			const { state, uiLoadpoints } = store;
 			return { ...state, uiLoadpoints: uiLoadpoints.value };
@@ -182,7 +189,7 @@ export default defineComponent({
 			this.ws.onmessage = (evt) => {
 				try {
 					const msg = JSON.parse(evt.data);
-					if (msg.startup) {
+					if (msg.startupCompleted) {
 						store.reset();
 					}
 					store.update(msg);
diff --git a/assets/js/views/Main.vue b/assets/js/views/Main.vue
index 9e4f60754..5ee1d5b52 100644
--- a/assets/js/views/Main.vue
+++ b/assets/js/views/Main.vue
@@ -1,6 +1,5 @@
 <template>
 	<Site
-		v-if="state.startup"
 		:notifications="notifications"
 		v-bind="state"
 		:selected-loadpoint-index="selectedLoadpointIndex"
diff --git a/cmd/root.go b/cmd/root.go
index 382f41fd2..d38852c07 100644
--- a/cmd/root.go
+++ b/cmd/root.go
@@ -157,8 +157,6 @@ func runRoot(cmd *cobra.Command, args []string) {
 		err = networkSettings(&conf.Network)
 	}
 
-	log.INFO.Printf("UI listening at :%d", conf.Network.Port)
-
 	// start broadcasting values
 	tee := new(util.Tee)
 	valueChan := make(chan util.Param, 64)
@@ -172,6 +170,21 @@ func runRoot(cmd *cobra.Command, args []string) {
 	socketHub := server.NewSocketHub()
 	httpd := server.NewHTTPd(fmt.Sprintf(":%d", conf.Network.Port), socketHub, customCssFile)
 
+	// start serving in background, watch for “routine‐only” errors
+	go func() {
+		if err := wrapFatalError(httpd.Server.ListenAndServe()); err != nil && err != http.ErrServerClosed {
+			log.FATAL.Println(err)
+			os.Exit(1)
+		}
+	}()
+	log.INFO.Printf("UI listening at :%d", conf.Network.Port)
+
+	// publish to UI
+	go socketHub.Run(pipe.NewDropper(ignoreEmpty).Pipe(tee.Attach()), cache)
+
+	// signal ui listening
+	valueChan <- util.Param{Key: keys.StartupCompleted, Val: false}
+
 	// metrics
 	if viper.GetBool("metrics") {
 		httpd.Router().Handle("/metrics", promhttp.Handler())
@@ -182,9 +195,6 @@ func runRoot(cmd *cobra.Command, args []string) {
 		httpd.Router().PathPrefix("/debug/").Handler(http.DefaultServeMux)
 	}
 
-	// publish to UI
-	go socketHub.Run(pipe.NewDropper(ignoreEmpty).Pipe(tee.Attach()), cache)
-
 	// capture log messages for UI
 	util.CaptureLogs(valueChan)
 
@@ -236,8 +246,10 @@ func runRoot(cmd *cobra.Command, args []string) {
 		}
 	}
 
-	// signal restart
-	valueChan <- util.Param{Key: keys.Startup, Val: true}
+	// signal devices initialized
+	valueChan <- util.Param{Key: keys.StartupCompleted, Val: true}
+	// show onboarding UI
+	valueChan <- util.Param{Key: keys.SetupRequired, Val: site == nil || len(site.Loadpoints()) == 0}
 
 	// setup mqtt publisher
 	if err == nil && conf.Mqtt.Broker != "" && conf.Mqtt.Topic != "" {
@@ -310,19 +322,6 @@ func runRoot(cmd *cobra.Command, args []string) {
 		once.Do(func() { close(stopC) }) // signal loop to end
 	}()
 
-	// wait for shutdown
-	go func() {
-		<-stopC
-
-		select {
-		case <-shutdownDoneC(): // wait for shutdown
-		case <-time.After(conf.Interval):
-		}
-
-		// exit code 1 on error
-		os.Exit(cast.ToInt(err != nil))
-	}()
-
 	// allow web access for vehicles
 	configureAuth(httpd.Router(), valueChan)
 
@@ -383,5 +382,14 @@ func runRoot(cmd *cobra.Command, args []string) {
 	// uds health check listener
 	go server.HealthListener(site)
 
-	log.FATAL.Println(wrapFatalError(httpd.ListenAndServe()))
+	// wait for shutdown
+	<-stopC
+
+	select {
+	case <-shutdownDoneC(): // wait for shutdown
+	case <-time.After(conf.Interval):
+	}
+
+	// exit code 1 on error
+	os.Exit(cast.ToInt(err != nil))
 }
diff --git a/core/keys/global.go b/core/keys/global.go
index f0769f55e..c028984ce 100644
--- a/core/keys/global.go
+++ b/core/keys/global.go
@@ -18,7 +18,8 @@ const (
 	Config             = "config"
 	Database           = "database"
 	Fatal              = "fatal"
-	Startup            = "startup"
+	StartupCompleted   = "startupCompleted" // false: starting, true: started
+	SetupRequired      = "setupRequired"    // initial setup is required (lp = 0), fresh installation
 	Plant              = "plant"
 	Telemetry          = "telemetry"
 	DemoMode           = "demoMode"
diff --git a/i18n/de.json b/i18n/de.json
index 30f259a28..53a07798b 100644
--- a/i18n/de.json
+++ b/i18n/de.json
@@ -1017,7 +1017,8 @@
     "message": "Keine Verbindung zum Server.",
     "restart": "Neustart",
     "restartNeeded": "Erforderlich, um Änderungen zu übernehmen.",
-    "restarting": "Server ist gleich wieder verfügbar."
+    "restarting": "Server ist gleich wieder verfügbar.",
+    "starting": "Server wird gestartet..."
   },
   "passwordModal": {
     "description": "Setze ein Passwort, um die Konfiguration zu schützen. Die Hauptansicht bleibt ohne Login zugänglich.",
@@ -1206,6 +1207,7 @@
     "configuration": "Konfiguration",
     "description": "Bitte überprüfe deine Konfigurationsdatei. Sollte dir die Fehlermeldung nicht weiterhelfen, suche in unseren {0} nach einer Lösung.",
     "discussions": "GitHub Diskussionen",
+    "editConfiguration": "Konfiguration bearbeiten",
     "fixAndRestart": "Behebe das Problem und starte den Server neu.",
     "hint": "Hinweis: Ein weiterer Grund könnte ein fehlerhaftes Gerät (Wechselrichter, Zähler, …) sein. Überprüfe deine Netzwerkverbindungen.",
     "lineError": "In {0} wurde ein Fehler gefunden.",
diff --git a/i18n/en.json b/i18n/en.json
index a6f0ca002..07fba2a4e 100644
--- a/i18n/en.json
+++ b/i18n/en.json
@@ -1018,7 +1018,8 @@
     "message": "Not connected to a server.",
     "restart": "Restart",
     "restartNeeded": "Required to apply changes.",
-    "restarting": "Server will be back in a moment."
+    "restarting": "Server will be back in a moment.",
+    "starting": "Starting server..."
   },
   "passwordModal": {
     "description": "Set a password to protect the configuration settings. Using the main screen is still possible without login.",
@@ -1207,6 +1208,7 @@
     "configuration": "Config",
     "description": "Please check your configuration file. If the error message does not help, check out the {0}.",
     "discussions": "GitHub Discussions",
+    "editConfiguration": "Edit configuration",
     "fixAndRestart": "Please fix the problem and restart the server.",
     "hint": "Note: It could also be you have a faulty device (inverter, meter, …). Check your network connections.",
     "lineError": "Error in {0}.",
diff --git a/tests/config-modbus-fields.spec.ts b/tests/config-modbus-fields.spec.ts
index 63b30cb2a..388da1af2 100644
--- a/tests/config-modbus-fields.spec.ts
+++ b/tests/config-modbus-fields.spec.ts
@@ -32,7 +32,7 @@ test.describe("modbus fields", async () => {
     const modal = await openMeterModal(page, "TCP Test");
     await expect(page.getByLabel("Network")).toBeChecked();
     await expect(page.getByLabel("TCP")).toBeChecked();
-    await expect(modal.getByLabel("IP address or hostname")).toHaveValue("192.168.1.10");
+    await expect(modal.getByLabel("IP address or hostname")).toHaveValue("192.0.2.1");
     await expect(modal.getByLabel("Port", { exact: true })).toHaveValue("5020");
     await expect(modal.getByLabel("Modbus ID")).toHaveValue("10");
   });
@@ -41,7 +41,7 @@ test.describe("modbus fields", async () => {
     const modal = await openMeterModal(page, "RTU/IP Test");
     await expect(page.getByLabel("Network")).toBeChecked();
     await expect(page.getByLabel("RTU")).toBeChecked();
-    await expect(modal.getByLabel("IP address or hostname")).toHaveValue("192.168.1.20");
+    await expect(modal.getByLabel("IP address or hostname")).toHaveValue("198.51.100.1");
     await expect(modal.getByLabel("Port", { exact: true })).toHaveValue("8899");
     await expect(modal.getByLabel("Modbus ID")).toHaveValue("20");
   });
diff --git a/tests/config-modbus-fields.sql b/tests/config-modbus-fields.sql
index 4f597bfeb..f31384522 100644
--- a/tests/config-modbus-fields.sql
+++ b/tests/config-modbus-fields.sql
@@ -15,8 +15,9 @@ CREATE TABLE `settings` (
   , PRIMARY KEY(`key`)
 );
 
-INSERT INTO configs(id, class, type, title, icon, product, value) VALUES(1, 2, 'template', 'TCP Test', '', 'SunSpec Inverter', '{"host":"192.168.1.10","id":10,"modbus":"tcpip","port":5020,"template":"sunspec-inverter","usage":"pv"}');
-INSERT INTO configs(id, class, type, title, icon, product, value) VALUES(2, 2, 'template', 'RTU/IP Test', '', 'SunSpec Inverter', '{"host":"192.168.1.20","id":20,"modbus":"rs485tcpip","port":8899,"template":"sunspec-inverter","usage":"pv"}');
+-- using RFC 5737 TEST-NET addresses (192.0.2.0/24, 198.51.100.0/24) that are guaranteed to fail connection attempts
+INSERT INTO configs(id, class, type, title, icon, product, value) VALUES(1, 2, 'template', 'TCP Test', '', 'SunSpec Inverter', '{"host":"192.0.2.1","id":10,"modbus":"tcpip","port":5020,"template":"sunspec-inverter","usage":"pv"}');
+INSERT INTO configs(id, class, type, title, icon, product, value) VALUES(2, 2, 'template', 'RTU/IP Test', '', 'SunSpec Inverter', '{"host":"198.51.100.1","id":20,"modbus":"rs485tcpip","port":8899,"template":"sunspec-inverter","usage":"pv"}');
 INSERT INTO configs(id, class, type, title, icon, product, value) VALUES(3, 2, 'template', 'Serial Test', '', 'SunSpec Inverter', '{"baudrate":19200,"comset":"8E1","device":"/dev/ttyUSB5","id":30,"modbus":"rs485serial","template":"sunspec-inverter","usage":"pv"}');
 
 INSERT INTO settings("key", value) VALUES('pvMeters', 'db:1,db:2,db:3');
diff --git a/tests/ws.spec.ts b/tests/ws.spec.ts
index 5d3af18c3..c03ea76a9 100644
--- a/tests/ws.spec.ts
+++ b/tests/ws.spec.ts
@@ -1,11 +1,13 @@
 import { test, expect } from "@playwright/test";
 import { start, stop, baseUrl } from "./evcc";
-test.use({ baseURL: baseUrl() });
 
-test.beforeAll(async () => {
+test.use({ baseURL: baseUrl() });
+test.describe.configure({ mode: "parallel" });
+
+test.beforeEach(async () => {
   await start("basics.evcc.yaml");
 });
-test.afterAll(async () => {
+test.afterEach(async () => {
   await stop();
 });