diff --git a/native/package.json b/native/package.json
index 4df0810..aea262d 100644
--- a/native/package.json
+++ b/native/package.json
@@ -1,6 +1,6 @@
 {
     "name": "kanbangit-native",
-    "version": "0.1.3",
+    "version": "0.1.4",
     "private": true,
     "type": "module",
     "scripts": {
@@ -24,5 +24,5 @@
     "devDependencies": {
         "@tauri-apps/cli": "2.11.4"
     },
-    "releaseNotes": "About KanbanGit and Software updates now show the installed app build number correctly."
+    "releaseNotes": "About KanbanGit and Software updates show the installed app build number correctly. Release publishing now handles Hetzner responses with empty error messages when updating the feed."
 }
diff --git a/native/publish-macos.mjs b/native/publish-macos.mjs
index a38fe02..0c12ce3 100644
--- a/native/publish-macos.mjs
+++ b/native/publish-macos.mjs
@@ -63,6 +63,14 @@ export function storageConfiguration(env = process.env) {
 
 const sha256 = (data) => createHash('sha256').update(data).digest('hex');
 
+function requiresExistingObjectCheck(error) {
+    // AWS CLI can crash while formatting Hetzner's empty error Message.
+    // This only permits a readback; content checks and conditional writes still apply.
+    return /\(PreconditionFailed\)|\(412\)|argument of type 'NoneType' is not (?:a container or )?iterable/.test(
+        error.message,
+    );
+}
+
 export async function publishMacos({
     env = process.env,
     directory,
@@ -116,13 +124,21 @@ export async function publishMacos({
         's3api',
     ];
     function s3(operation, args) {
-        return run('aws', [
-            ...common,
-            operation,
-            '--bucket',
-            storage.bucket,
-            ...args,
-        ]);
+        try {
+            return run('aws', [
+                ...common,
+                operation,
+                '--bucket',
+                storage.bucket,
+                ...args,
+            ]);
+        } catch (error) {
+            const keyIndex = args.indexOf('--key');
+            const key = keyIndex >= 0 ? ` ${args[keyIndex + 1]}` : '';
+            throw new Error(`S3 ${operation}${key}: ${error.message}`, {
+                cause: error,
+            });
+        }
     }
     const versioningOutput = s3('get-bucket-versioning', [
         '--output',
@@ -213,7 +229,7 @@ export async function publishMacos({
                 `sha256=${sha256(contents)}`,
             ]);
         } catch (error) {
-            if (!/\(PreconditionFailed\)|\(412\)/.test(error.message)) {
+            if (!requiresExistingObjectCheck(error)) {
                 throw error;
             }
             const existing = join(staging, `existing-${name}`);
@@ -301,7 +317,7 @@ export async function publishMacos({
         try {
             publishLatest(['--if-none-match', '*']);
         } catch (error) {
-            if (!/\(PreconditionFailed\)|\(412\)/.test(error.message)) {
+            if (!requiresExistingObjectCheck(error)) {
                 throw error;
             }
             const previousFile = join(staging, 'previous-latest.json');
diff --git a/native/src-tauri/Cargo.lock b/native/src-tauri/Cargo.lock
index c69890d..2bb4dd3 100644
--- a/native/src-tauri/Cargo.lock
+++ b/native/src-tauri/Cargo.lock
@@ -1770,7 +1770,7 @@ dependencies = [
 
 [[package]]
 name = "kanbangit-native"
-version = "0.1.3"
+version = "0.1.4"
 dependencies = [
  "semver",
  "serde",
diff --git a/native/src-tauri/Cargo.toml b/native/src-tauri/Cargo.toml
index badf744..30e4a59 100644
--- a/native/src-tauri/Cargo.toml
+++ b/native/src-tauri/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "kanbangit-native"
-version = "0.1.3"
+version = "0.1.4"
 description = "KanbanGit native application"
 edition = "2021"
 publish = false
diff --git a/native/src-tauri/tauri.conf.json b/native/src-tauri/tauri.conf.json
index 6cc217e..ad00e5f 100644
--- a/native/src-tauri/tauri.conf.json
+++ b/native/src-tauri/tauri.conf.json
@@ -1,7 +1,7 @@
 {
     "$schema": "https://schema.tauri.app/config/2",
     "productName": "KanbanGit",
-    "version": "0.1.3",
+    "version": "0.1.4",
     "identifier": "de.kanbangit.desktop",
     "build": {
         "frontendDist": "../ui"
@@ -25,7 +25,7 @@
         ],
         "macOS": {
             "minimumSystemVersion": "14.0",
-            "bundleVersion": "3",
+            "bundleVersion": "4",
             "dmg": {
                 "windowSize": {
                     "width": 660,
diff --git a/native/tests/publish-macos.test.js b/native/tests/publish-macos.test.js
index 5b9e59e..0745f37 100644
--- a/native/tests/publish-macos.test.js
+++ b/native/tests/publish-macos.test.js
@@ -8,7 +8,10 @@ import test from 'node:test';
 import { publishMacos, storageConfiguration } from '../publish-macos.mjs';
 import { signedFixture } from './updater-fixture.mjs';
 
-function fixture(t) {
+function fixture(
+    t,
+    conflictMessage = 'aws failed: (PreconditionFailed) object exists',
+) {
     const directory = mkdtempSync(join(tmpdir(), 'kanbangit-upload-test-'));
     t.after(() => rmSync(directory, { recursive: true, force: true }));
     const metadata = {
@@ -60,9 +63,7 @@ function fixture(t) {
             }
             if (objects.has(key)) {
                 if (!args.includes('--if-match')) {
-                    throw new Error(
-                        'aws failed: (PreconditionFailed) object exists',
-                    );
+                    throw new Error(conflictMessage);
                 }
                 assert.equal(value('--if-match'), '"previous-etag"');
             }
@@ -427,3 +428,86 @@ test('concurrent feed replacement fails without overwriting the winner', async (
     await assert.rejects(publishMacos(f), /concurrent publication/);
     assert.equal(JSON.parse(f.objects.get(key)).version, '2.0.0');
 });
+
+for (const message of [
+    "aws failed (exit 255). aws: [ERROR]: argument of type 'NoneType' is not a container or iterable",
+    "aws failed (exit 255). argument of type 'NoneType' is not iterable",
+]) {
+    test(`empty S3 error message permits verified promotion and identical retry: ${message}`, async (t) => {
+        const f = fixture(t, message);
+        const key = `releases/macos/${f.metadata.target}/latest.json`;
+        f.objects.set(key, Buffer.from(JSON.stringify({ version: '1.0.0' })));
+        await publishMacos(f);
+        assert.equal(JSON.parse(f.objects.get(key)).version, '1.2.3');
+        const published = [...f.objects.entries()];
+        await publishMacos(f);
+        assert.deepEqual([...f.objects.entries()], published);
+    });
+
+    test(`empty S3 error cannot bypass immutable content checks: ${message}`, async (t) => {
+        const f = fixture(t, message);
+        const key = `releases/macos/${f.metadata.target}/1.2.3/${f.metadata.filename}`;
+        f.objects.set(key, Buffer.from('different existing release'));
+        await assert.rejects(publishMacos(f), /bump the app version/);
+        assert.equal(f.objects.size, 1);
+        assert.equal(
+            f.objects.get(key).toString(),
+            'different existing release',
+        );
+    });
+
+    for (const previous of [
+        { version: '2.0.0' },
+        { version: '1.2.3', notes: 'different' },
+    ]) {
+        test(`empty S3 error cannot bypass feed conflict checks ${previous.version}: ${message}`, async (t) => {
+            const f = fixture(t, message);
+            const key = `releases/macos/${f.metadata.target}/latest.json`;
+            const original = Buffer.from(JSON.stringify(previous));
+            f.objects.set(key, original);
+            await assert.rejects(publishMacos(f), /downgrade|differs/);
+            assert.deepEqual(f.objects.get(key), original);
+        });
+    }
+
+    test(`empty S3 error aborts when existing contents cannot be read: ${message}`, async (t) => {
+        const f = fixture(t, message);
+        const run = f.run;
+        f.run = (command, args) => {
+            if (args.includes('put-object')) {
+                throw new Error(message);
+            }
+            if (args.includes('get-object')) {
+                throw new Error('AccessDenied');
+            }
+            return run(command, args);
+        };
+        await assert.rejects(publishMacos(f), /S3 get-object .*AccessDenied/);
+        assert.equal(f.objects.size, 0);
+    });
+
+    test(`empty S3 error during conditional replacement preserves a concurrent winner: ${message}`, async (t) => {
+        const f = fixture(t, message);
+        const key = `releases/macos/${f.metadata.target}/latest.json`;
+        f.objects.set(key, Buffer.from(JSON.stringify({ version: '1.0.0' })));
+        const run = f.run;
+        let attempts = 0;
+        f.run = (command, args) => {
+            if (args.includes('--if-match')) {
+                attempts++;
+                f.objects.set(
+                    key,
+                    Buffer.from(JSON.stringify({ version: '2.0.0' })),
+                );
+                throw new Error(message);
+            }
+            return run(command, args);
+        };
+        await assert.rejects(
+            publishMacos(f),
+            /S3 put-object .*latest.json: .*NoneType/,
+        );
+        assert.equal(attempts, 1);
+        assert.equal(JSON.parse(f.objects.get(key)).version, '2.0.0');
+    });
+}