diff --git a/apps/desktop/src/i18n/backend-errors.ts b/apps/desktop/src/i18n/backend-errors.ts
index 389fe4f771..f08427413b 100644
--- a/apps/desktop/src/i18n/backend-errors.ts
+++ b/apps/desktop/src/i18n/backend-errors.ts
@@ -92,7 +92,7 @@ const patterns: [RegExp, string][] = [
   [/^Plugin update blocked by active connections: ([\s\S]+)$/, "pluginPlatform.updateBlockedByConnections"],
   [/^(.+?) driver is not installed\. Please install it from the Driver Manager\.$/, "connection.driverNotInstalled"],
   [/^JRE (.+?) runtime is not installed\. Please install it from the Driver Manager\.$/, "connection.jreNotInstalled"],
-  [/^System Java runtime was not found on PATH\. Please install Java or choose a custom Java executable\.$/, "connection.systemJavaNotFound"],
+  [/^System Java runtime was not found:/, "connection.systemJavaNotFound"],
   [/^Custom Java runtime path is empty\. Please choose a Java executable\.$/, "connection.customJavaPathEmpty"],
   [/^Agent requires Java 21, but DBX started it with an older Java runtime\. Use DBX managed JRE 21 or select a Java 21 executable in Driver Manager\./, "connection.agentJavaTooOld"],
   [/^JDBC plugin is not installed\. Install the optional JDBC plugin to use this connection\.$/, "connection.jdbcPluginNotInstalled"],
diff --git a/apps/desktop/src/i18n/locales/az.ts b/apps/desktop/src/i18n/locales/az.ts
index 57126c1779..84092d50fe 100644
--- a/apps/desktop/src/i18n/locales/az.ts
+++ b/apps/desktop/src/i18n/locales/az.ts
@@ -1090,7 +1090,7 @@ export default withEnglishFallback({
     driverNotInstalled: "{driver} drayveri quraşdırılmayıb. Onu drayver menecerindən quraşdırın.",
     phoenixDriverNotInstalled: "Apache Phoenix JDBC drayveri quraşdırılmayıb. Onu drayver menecerindən quraşdırın, sonra yenidən cəhd edin.",
     jreNotInstalled: "JRE {jre} icra mühiti quraşdırılmayıb. Onu drayver menecerindən quraşdırın.",
-    systemJavaNotFound: "Sistemin Java icra mühiti PATH-də tapılmadı. Java quraşdırın və ya xüsusi Java icra faylı seçin.",
+    systemJavaNotFound: "Sistemin Java icra mühiti JAVA_HOME və ya PATH-də tapılmadı. Java quraşdırın və ya xüsusi Java icra faylı seçin.",
     customJavaPathEmpty: "Xüsusi Java icra mühitinin yolu boşdur. Java icra faylı seçin.",
     agentJavaTooOld: "Bu drayver Java 21 tələb edir. DBX tərəfindən idarə olunan JRE 21-dən istifadə edin və ya drayver menecerində Java 21 icra faylı seçin.",
     agentDriverUpdateConnectionHint: "Bu əlaqə üçün daxili drayver yeniləməsi mövcuddur. Əlaqə xətası köhnəlmiş yerli drayverlə bağlı ola bilər. Drayver menecerində müvafiq drayveri yeniləyin, sonra yenidən cəhd edin.",
@@ -8102,7 +8102,7 @@ export default withEnglishFallback({
     saving: "Yadda saxlanılır...",
     customJavaPathPlaceholder: "/path/to/java və ya /path/to/jdk",
     choose: "Seç",
-    systemJavaHint: "Cari PATH-dəki java-dan istifadə et.",
+    systemJavaHint: "Əvvəlcə JAVA_HOME, sonra PATH-dəki java-dan istifadə et.",
     jreRuntimeTitle: "JRE {jre} icra mühiti",
     notInstalled: "Quraşdırılmayıb",
     reinstalling: "Yenidən quraşdırılır",
diff --git a/apps/desktop/src/i18n/locales/en.ts b/apps/desktop/src/i18n/locales/en.ts
index 1875be9fc1..84b1b31b8c 100644
--- a/apps/desktop/src/i18n/locales/en.ts
+++ b/apps/desktop/src/i18n/locales/en.ts
@@ -1244,7 +1244,7 @@ export default {
     driverNotInstalled: "{driver} driver is not installed. Please install it from the Driver Manager.",
     phoenixDriverNotInstalled: "The Apache Phoenix JDBC driver is not installed. Install it from the Driver Manager, then retry.",
     jreNotInstalled: "JRE {jre} runtime is not installed. Please install it from the Driver Manager.",
-    systemJavaNotFound: "System Java runtime was not found on PATH. Please install Java or choose a custom Java executable.",
+    systemJavaNotFound: "System Java runtime was not found in JAVA_HOME or PATH. Please install Java or choose a custom Java executable.",
     customJavaPathEmpty: "Custom Java runtime path is empty. Please choose a Java executable.",
     agentJavaTooOld: "This driver requires Java 21. Use DBX managed JRE 21 or select a Java 21 executable in Driver Manager.",
     agentDriverUpdateConnectionHint: "A built-in driver update is available for this connection. The connection failure may be related to an outdated local driver. Update the corresponding driver in Driver Manager, then retry.",
@@ -8337,7 +8337,7 @@ export default {
     saving: "Saving...",
     customJavaPathPlaceholder: "/path/to/java or /path/to/jdk",
     choose: "Choose",
-    systemJavaHint: "Use java from the current PATH.",
+    systemJavaHint: "Resolve java from JAVA_HOME first, then PATH.",
     jreRuntimeTitle: "JRE {jre} Runtime",
     notInstalled: "Not installed",
     reinstalling: "Reinstalling",
diff --git a/apps/desktop/src/i18n/locales/es.ts b/apps/desktop/src/i18n/locales/es.ts
index cbbb0b60df..544b8647f1 100644
--- a/apps/desktop/src/i18n/locales/es.ts
+++ b/apps/desktop/src/i18n/locales/es.ts
@@ -1010,7 +1010,7 @@ export default withEnglishFallback({
     driverNotInstalled: "El controlador {driver} no está instalado. Instálelo desde el Administrador de controladores.",
     phoenixDriverNotInstalled: "El controlador JDBC de Apache Phoenix no está instalado. Instálelo desde el Administrador de controladores y vuelva a intentarlo.",
     jreNotInstalled: "El entorno JRE {jre} no está instalado. Instálelo desde el Administrador de controladores.",
-    systemJavaNotFound: "No se encontró Java en el PATH del sistema. Instale Java o elija un ejecutable personalizado.",
+    systemJavaNotFound: "No se encontró Java en JAVA_HOME ni en el PATH del sistema. Instale Java o elija un ejecutable personalizado.",
     customJavaPathEmpty: "La ruta de Java personalizada está vacía. Elija un ejecutable de Java.",
     agentJavaTooOld: "Este controlador requiere Java 21. Use el JRE 21 administrado por DBX o seleccione un ejecutable Java 21 en el Administrador de controladores.",
     agentDriverUpdateConnectionHint:
@@ -7872,7 +7872,7 @@ export default withEnglishFallback({
     saving: "Guardando...",
     customJavaPathPlaceholder: "/ruta/a/java o /ruta/a/jdk",
     choose: "Seleccionar",
-    systemJavaHint: "Usa java del PATH actual.",
+    systemJavaHint: "Usa java de JAVA_HOME y, si no, del PATH.",
     jreRuntimeTitle: "Runtime JRE {jre}",
     notInstalled: "No instalado",
     reinstalling: "Reinstalando",
diff --git a/apps/desktop/src/i18n/locales/it.ts b/apps/desktop/src/i18n/locales/it.ts
index b643cde4b9..f8d5b5ae27 100644
--- a/apps/desktop/src/i18n/locales/it.ts
+++ b/apps/desktop/src/i18n/locales/it.ts
@@ -1009,7 +1009,7 @@ export default withEnglishFallback({
     driverNotInstalled: "Il driver {driver} non è installato. Installalo da Gestione Driver.",
     phoenixDriverNotInstalled: "Il driver JDBC di Apache Phoenix non è installato. Installalo da Gestione Driver e riprova.",
     jreNotInstalled: "Il runtime JRE {jre} non è installato. Installalo da Gestione Driver.",
-    systemJavaNotFound: "Runtime Java di sistema non trovato in PATH. Installa Java o scegli un eseguibile Java personalizzato.",
+    systemJavaNotFound: "Runtime Java di sistema non trovato in JAVA_HOME o in PATH. Installa Java o scegli un eseguibile Java personalizzato.",
     customJavaPathEmpty: "Il percorso del runtime Java personalizzato è vuoto. Scegli un eseguibile Java.",
     agentJavaTooOld: "Questo driver richiede Java 21. Usa il JRE 21 gestito da DBX o seleziona un eseguibile Java 21 in Gestione Driver.",
     agentDriverUpdateConnectionHint: "È disponibile un aggiornamento del driver integrato per questa connessione. Il problema di connessione potrebbe essere correlato a un driver locale obsoleto. Aggiorna il driver corrispondente in Gestione Driver e riprova.",
@@ -7872,7 +7872,7 @@ export default withEnglishFallback({
     saving: "Salvataggio...",
     customJavaPathPlaceholder: "/percorso/per/java o /percorso/per/jdk",
     choose: "Scegli",
-    systemJavaHint: "Usa java dal PATH corrente.",
+    systemJavaHint: "Usa java da JAVA_HOME, poi dal PATH.",
     jreRuntimeTitle: "Runtime JRE {jre}",
     notInstalled: "Non installato",
     reinstalling: "Reinstallazione in corso",
diff --git a/apps/desktop/src/i18n/locales/ja.ts b/apps/desktop/src/i18n/locales/ja.ts
index 6cdbac7175..3dcaf5b5b5 100644
--- a/apps/desktop/src/i18n/locales/ja.ts
+++ b/apps/desktop/src/i18n/locales/ja.ts
@@ -975,7 +975,7 @@ export default withEnglishFallback({
     driverNotInstalled: "{driver} ドライバーがインストールされていません。ドライバーマネージャーからインストールしてください。",
     phoenixDriverNotInstalled: "Apache Phoenix JDBC ドライバーがインストールされていません。ドライバーマネージャーからインストールして、再試行してください。",
     jreNotInstalled: "JRE {jre} ランタイムがインストールされていません。ドライバーマネージャーからインストールしてください。",
-    systemJavaNotFound: "システムJavaランタイムがPATHに見つかりませんでした。Javaをインストールするか、カスタムJava実行ファイルを選択してください。",
+    systemJavaNotFound: "システムJavaランタイムがJAVA_HOMEまたはPATHに見つかりませんでした。Javaをインストールするか、カスタムJava実行ファイルを選択してください。",
     customJavaPathEmpty: "カスタムJavaランタイムのパスが空です。Java実行ファイルを選択してください。",
     agentJavaTooOld: "このドライバーにはJava 21が必要です。ドライバーマネージャーでDBX管理JRE 21を使用するか、Java 21実行ファイルを選択してください。",
     agentDriverUpdateConnectionHint: "この接続で使用中の内蔵ドライバに更新が利用可能です。接続失敗はローカルドライバの旧版が原因の可能性があります。ドライバマネージャーで該当ドライバを更新してから再試行してください。",
@@ -7924,7 +7924,7 @@ export default withEnglishFallback({
     saving: "保存中...",
     customJavaPathPlaceholder: "/path/to/java or /path/to/jdk",
     choose: "選択",
-    systemJavaHint: "現在のPATHからJavaを使用します。",
+    systemJavaHint: "JAVA_HOME を優先し、次に PATH の Java を使用します。",
     jreRuntimeTitle: "JRE {jre} ランタイム",
     notInstalled: "未インストール",
     reinstalling: "再インストール中",
diff --git a/apps/desktop/src/i18n/locales/ko.ts b/apps/desktop/src/i18n/locales/ko.ts
index 503cc5ec5e..afbec7deb6 100644
--- a/apps/desktop/src/i18n/locales/ko.ts
+++ b/apps/desktop/src/i18n/locales/ko.ts
@@ -1122,7 +1122,7 @@ export default withEnglishFallback({
     driverNotInstalled: "{driver} 드라이버가 설치되지 않았습니다. 드라이버 관리자에서 설치하세요.",
     phoenixDriverNotInstalled: "Apache Phoenix JDBC 드라이버가 설치되지 않았습니다. 드라이버 관리자에서 설치한 후 다시 시도하세요.",
     jreNotInstalled: "JRE {jre} 런타임이 설치되지 않았습니다. 드라이버 관리자에서 설치하세요.",
-    systemJavaNotFound: "PATH에서 시스템 Java 런타임을 찾을 수 없습니다. Java를 설치하거나 사용자 지정 Java 실행 파일을 선택하세요.",
+    systemJavaNotFound: "JAVA_HOME 또는 PATH에서 시스템 Java 런타임을 찾을 수 없습니다. Java를 설치하거나 사용자 지정 Java 실행 파일을 선택하세요.",
     customJavaPathEmpty: "사용자 지정 Java 런타임 경로가 비어 있습니다. Java 실행 파일을 선택하세요.",
     agentJavaTooOld: "이 드라이버는 Java 21이 필요합니다. DBX 관리 JRE 21을 사용하거나 드라이버 관리자에서 Java 21 실행 파일을 선택하세요.",
     agentDriverUpdateConnectionHint: "이 연결에 사용 가능한 내장 드라이버 업데이트가 있습니다. 연결 실패가 오래된 로컬 드라이버와 관련이 있을 수 있습니다. 드라이버 관리자에서 해당 드라이버를 업데이트한 후 다시 시도하세요.",
@@ -7604,7 +7604,7 @@ export default withEnglishFallback({
     saving: "저장 중...",
     customJavaPathPlaceholder: "/path/to/java 또는 /path/to/jdk",
     choose: "선택",
-    systemJavaHint: "현재 PATH의 java를 사용합니다.",
+    systemJavaHint: "JAVA_HOME을 우선 사용하고, 없으면 PATH의 java를 사용합니다.",
     jreRuntimeTitle: "JRE {jre} 런타임",
     notInstalled: "설치되지 않음",
     reinstalling: "다시 설치 중",
diff --git a/apps/desktop/src/i18n/locales/pt-BR.ts b/apps/desktop/src/i18n/locales/pt-BR.ts
index b85efa8ad1..2d40a569f1 100644
--- a/apps/desktop/src/i18n/locales/pt-BR.ts
+++ b/apps/desktop/src/i18n/locales/pt-BR.ts
@@ -1010,7 +1010,7 @@ export default withEnglishFallback({
     driverNotInstalled: "O driver {driver} não está instalado. Instale-o pelo Gerenciador de Drivers.",
     phoenixDriverNotInstalled: "O driver JDBC do Apache Phoenix não está instalado. Instale-o pelo Gerenciador de Drivers e tente novamente.",
     jreNotInstalled: "O runtime JRE {jre} não está instalado. Instale-o pelo Gerenciador de Drivers.",
-    systemJavaNotFound: "O runtime Java do sistema não foi encontrado no PATH. Instale o Java ou escolha um executável Java personalizado.",
+    systemJavaNotFound: "O runtime Java do sistema não foi encontrado no JAVA_HOME nem no PATH. Instale o Java ou escolha um executável Java personalizado.",
     customJavaPathEmpty: "O caminho do runtime Java personalizado está vazio. Escolha um executável Java.",
     agentJavaTooOld: "Este driver requer Java 21. Use o JRE 21 gerenciado pelo DBX ou selecione um executável Java 21 no Gerenciador de Drivers.",
     agentDriverUpdateConnectionHint: "Há uma atualização de driver integrada disponível para esta conexão. A falha de conexão pode estar relacionada a um driver local desatualizado. Atualize o driver correspondente no Gerenciador de Drivers e tente novamente.",
@@ -7874,7 +7874,7 @@ export default withEnglishFallback({
     saving: "Salvando...",
     customJavaPathPlaceholder: "/caminho/para/java ou /caminho/para/jdk",
     choose: "Escolher",
-    systemJavaHint: "Usar o java do PATH atual.",
+    systemJavaHint: "Usar o java do JAVA_HOME e, se não houver, do PATH.",
     jreRuntimeTitle: "Runtime da JRE {jre}",
     notInstalled: "Não instalado",
     reinstalling: "Reinstalando",
diff --git a/apps/desktop/src/i18n/locales/tr.ts b/apps/desktop/src/i18n/locales/tr.ts
index e10e3ea3c5..0b3eb1d71f 100644
--- a/apps/desktop/src/i18n/locales/tr.ts
+++ b/apps/desktop/src/i18n/locales/tr.ts
@@ -1092,7 +1092,7 @@ export default withEnglishFallback({
     driverNotInstalled: "{driver} sürücüsü kurulu değil. Lütfen Sürücü Yöneticisi'nden kurun.",
     phoenixDriverNotInstalled: "Apache Phoenix JDBC sürücüsü kurulu değil. Sürücü Yöneticisi'nden kurup tekrar deneyin.",
     jreNotInstalled: "JRE {jre} çalışma zamanı kurulu değil. Lütfen Sürücü Yöneticisi'nden kurun.",
-    systemJavaNotFound: "Sistem Java çalışma zamanı PATH üzerinde bulunamadı. Lütfen Java kurun veya özel bir Java çalıştırılabiliri seçin.",
+    systemJavaNotFound: "Sistem Java çalışma zamanı JAVA_HOME veya PATH üzerinde bulunamadı. Lütfen Java kurun veya özel bir Java çalıştırılabiliri seçin.",
     customJavaPathEmpty: "Özel Java çalışma zamanı yolu boş. Lütfen bir Java çalıştırılabiliri seçin.",
     agentJavaTooOld: "Bu sürücü Java 21 gerektirir. DBX tarafından yönetilen JRE 21'i kullanın veya Sürücü Yöneticisi'nde bir Java 21 çalıştırılabiliri seçin.",
     agentDriverUpdateConnectionHint: "Bu bağlantı için yerleşik bir sürücü güncellemesi mevcut. Bağlantı hatası, güncel olmayan yerel sürücüyle ilgili olabilir. Sürücü Yöneticisi'nde ilgili sürücüyü güncelleyip tekrar deneyin.",
@@ -7957,7 +7957,7 @@ export default withEnglishFallback({
     saving: "Kaydediliyor...",
     customJavaPathPlaceholder: "/path/to/java veya /path/to/jdk",
     choose: "Seç",
-    systemJavaHint: "Geçerli PATH üzerindeki java'yı kullan.",
+    systemJavaHint: "Önce JAVA_HOME, sonra PATH üzerindeki java'yı kullan.",
     jreRuntimeTitle: "JRE {jre} Çalışma Zamanı",
     notInstalled: "Kurulu değil",
     reinstalling: "Yeniden kuruluyor",
diff --git a/apps/desktop/src/i18n/locales/zh-CN.ts b/apps/desktop/src/i18n/locales/zh-CN.ts
index 06e3d553d3..e8a2353fc3 100644
--- a/apps/desktop/src/i18n/locales/zh-CN.ts
+++ b/apps/desktop/src/i18n/locales/zh-CN.ts
@@ -1162,7 +1162,7 @@ export default withEnglishFallback({
     driverNotInstalled: "{driver} 驱动未安装，请在驱动管理器中安装。",
     phoenixDriverNotInstalled: "Apache Phoenix JDBC 驱动未安装，请在驱动管理器中安装后重试。",
     jreNotInstalled: "JRE {jre} 运行环境未安装，请在驱动管理器中安装。",
-    systemJavaNotFound: "未在 PATH 中找到系统 Java 运行环境，请安装 Java 或选择自定义 Java 可执行文件。",
+    systemJavaNotFound: "未在 JAVA_HOME 或 PATH 中找到系统 Java 运行环境，请安装 Java 或选择自定义 Java 可执行文件。",
     customJavaPathEmpty: "自定义 Java 运行环境路径为空，请选择 Java 可执行文件。",
     agentJavaTooOld: "该驱动需要 Java 21。请在驱动管理器中使用 DBX 托管 JRE 21，或选择 Java 21 可执行文件。",
     agentDriverUpdateConnectionHint: "当前连接使用的内置驱动有可用更新，连接失败可能与本地驱动版本过旧有关。请在「驱动管理」中更新对应驱动后重试。",
@@ -8309,7 +8309,7 @@ export default withEnglishFallback({
     saving: "保存中...",
     customJavaPathPlaceholder: "/path/to/java 或 /path/to/jdk",
     choose: "选择",
-    systemJavaHint: "使用当前环境 PATH 中的 java。",
+    systemJavaHint: "优先使用 JAVA_HOME，其次为 PATH 中的 java。",
     jreRuntimeTitle: "JRE {jre} 运行时",
     notInstalled: "未安装",
     reinstalling: "重装中",
diff --git a/apps/desktop/src/i18n/locales/zh-TW.ts b/apps/desktop/src/i18n/locales/zh-TW.ts
index 5e787a3b10..88b3edb413 100644
--- a/apps/desktop/src/i18n/locales/zh-TW.ts
+++ b/apps/desktop/src/i18n/locales/zh-TW.ts
@@ -1019,7 +1019,7 @@ export default withEnglishFallback({
     driverNotInstalled: "{driver} 驅動程式未安裝，請在驅動程式管理器中安裝。",
     phoenixDriverNotInstalled: "Apache Phoenix JDBC 驅動程式未安裝，請在驅動程式管理器中安裝後再試。",
     jreNotInstalled: "JRE {jre} 執行環境未安裝，請在驅動程式管理器中安裝。",
-    systemJavaNotFound: "未在 PATH 中找到系統 Java 執行環境，請安裝 Java 或選擇自訂 Java 可執行檔。",
+    systemJavaNotFound: "未在 JAVA_HOME 或 PATH 中找到系統 Java 執行環境，請安裝 Java 或選擇自訂 Java 可執行檔。",
     customJavaPathEmpty: "自訂 Java 執行環境路徑為空，請選擇 Java 可執行檔。",
     agentJavaTooOld: "此驅動程式需要 Java 21。請在驅動程式管理器中使用 DBX 託管 JRE 21，或選擇 Java 21 可執行檔。",
     agentDriverUpdateConnectionHint: "目前連線使用的內建驅動有可用更新，連線失敗可能與本機驅動版本過舊有關。請在「驅動管理」中更新對應驅動後重試。",
@@ -7179,7 +7179,7 @@ export default withEnglishFallback({
     saving: "儲存中……",
     customJavaPathPlaceholder: "/path/to/java 或 /path/to/jdk",
     choose: "選擇",
-    systemJavaHint: "使用目前環境 PATH 中的 java。",
+    systemJavaHint: "優先使用 JAVA_HOME，其次為 PATH 中的 java。",
     jreRuntimeTitle: "JRE {jre} 執行環境",
     notInstalled: "未安裝",
     reinstalling: "重新安裝中",
diff --git a/crates/dbx-drivers/src/agent_manager.rs b/crates/dbx-drivers/src/agent_manager.rs
index be2092a44c..9d37cf5e52 100644
--- a/crates/dbx-drivers/src/agent_manager.rs
+++ b/crates/dbx-drivers/src/agent_manager.rs
@@ -297,11 +297,56 @@ mod tests {
     #[test]
     fn resolves_system_java_runtime_from_path() {
         let manager = test_manager("system");
-        let system_java = manager.base_dir().join("bin").join(if cfg!(windows) { "java.exe" } else { "java" });
+        let system_java = manager.base_dir().join("bin").join(java_executable_name());
         touch(&system_java);
         let path = std::env::join_paths([system_java.parent().unwrap()]).unwrap();
 
-        assert_eq!(resolve_system_java_path(Some(path.as_os_str())).unwrap(), system_java);
+        assert_eq!(resolve_system_java_path(None, Some(path.as_os_str())).unwrap(), system_java);
+    }
+
+    #[test]
+    fn resolves_system_java_runtime_from_java_home() {
+        let manager = test_manager("system-home");
+        let java_home = manager.base_dir().join("jdk");
+        let system_java = java_home.join("bin").join(java_executable_name());
+        touch(&system_java);
+        // PATH deliberately points somewhere else: JAVA_HOME is the explicit
+        // declaration and must win.
+        let other_bin = manager.base_dir().join("other-bin");
+        let other_java = other_bin.join(java_executable_name());
+        touch(&other_java);
+        let path = std::env::join_paths([&other_bin]).unwrap();
+
+        assert_eq!(resolve_system_java_path(Some(java_home.as_os_str()), Some(path.as_os_str())).unwrap(), system_java);
+    }
+
+    #[test]
+    fn stale_java_home_falls_back_to_path() {
+        let manager = test_manager("system-stale-home");
+        let system_java = manager.base_dir().join("bin").join(java_executable_name());
+        touch(&system_java);
+        let path = std::env::join_paths([system_java.parent().unwrap()]).unwrap();
+        let dangling = manager.base_dir().join("removed-jdk");
+
+        assert_eq!(resolve_system_java_path(Some(dangling.as_os_str()), Some(path.as_os_str())).unwrap(), system_java);
+        assert!(resolve_system_java_path(Some(dangling.as_os_str()), None).is_none());
+        assert!(resolve_system_java_path(Some(OsStr::new("")), None).is_none());
+    }
+
+    #[test]
+    fn system_java_missing_error_names_the_checked_sources() {
+        let dangling = std::env::temp_dir().join("dbx-missing-jdk");
+        let path = std::env::join_paths([std::env::temp_dir()]).unwrap();
+
+        let message = system_java_missing_error(Some(dangling.as_os_str()), Some(path.as_os_str()));
+        assert!(message.contains(&dangling.display().to_string()), "{message}");
+        assert!(message.contains(java_executable_name()), "{message}");
+        assert!(message.contains("no java in the 1 PATH entries checked"), "{message}");
+        assert!(message.contains("restart dbx"), "{message}");
+
+        let unset = system_java_missing_error(None, None);
+        assert!(unset.contains("JAVA_HOME is not set"), "{unset}");
+        assert!(unset.contains("PATH is not set"), "{unset}");
     }
 
     #[tokio::test]
@@ -1042,10 +1087,12 @@ impl AgentManager {
                 }
                 Ok(self.jre_java_path(jre_key))
             }
-            JavaRuntimeMode::System => resolve_system_java_path(None).ok_or_else(|| {
-                "System Java runtime was not found on PATH. Please install Java or choose a custom Java executable."
-                    .to_string()
-            }),
+            JavaRuntimeMode::System => {
+                let java_home = std::env::var_os(JAVA_HOME_ENV);
+                let path_var = std::env::var_os(PATH_ENV);
+                resolve_system_java_path(java_home.as_deref(), path_var.as_deref())
+                    .ok_or_else(|| system_java_missing_error(java_home.as_deref(), path_var.as_deref()))
+            }
             JavaRuntimeMode::Custom => {
                 let path = state
                     .java_runtime
@@ -1238,32 +1285,81 @@ fn java_executable_name() -> &'static str {
     }
 }
 
-fn resolve_custom_java_path(path: &str) -> Result<PathBuf, String> {
-    let raw = PathBuf::from(path);
-    if is_executable_file(&raw) {
-        return Ok(raw);
+/// Locate `java` under a JDK/JRE root. Accepts the conventional `bin/java`
+/// layout, a macOS bundle (`Contents/Home/bin/java`), and a path that already
+/// points at the executable itself.
+fn resolve_java_under_root(root: &Path) -> Option<PathBuf> {
+    if is_executable_file(root) {
+        return Some(root.to_path_buf());
     }
 
-    let flat = raw.join("bin").join(java_executable_name());
+    let flat = root.join("bin").join(java_executable_name());
     if is_executable_file(&flat) {
-        return Ok(flat);
+        return Some(flat);
     }
 
-    let macos = raw.join("Contents").join("Home").join("bin").join(java_executable_name());
+    let macos = root.join("Contents").join("Home").join("bin").join(java_executable_name());
     if is_executable_file(&macos) {
-        return Ok(macos);
+        return Some(macos);
     }
 
-    Err(format!("Custom Java runtime does not exist or is not a Java executable: {}", raw.display()))
+    None
 }
 
-fn resolve_system_java_path(path_var: Option<&OsStr>) -> Option<PathBuf> {
-    let path_var = path_var.map(|p| p.to_owned()).or_else(|| std::env::var_os("PATH"))?;
-    std::env::split_paths(&path_var)
+fn resolve_custom_java_path(path: &str) -> Result<PathBuf, String> {
+    let raw = PathBuf::from(path);
+    resolve_java_under_root(&raw)
+        .ok_or_else(|| format!("Custom Java runtime does not exist or is not a Java executable: {}", raw.display()))
+}
+
+const JAVA_HOME_ENV: &str = "JAVA_HOME";
+const PATH_ENV: &str = "PATH";
+
+/// Resolve the "system" Java runtime from the user's own environment:
+/// `JAVA_HOME` first (their explicit declaration), then the first `java` on
+/// `PATH`. A `JAVA_HOME` that no longer contains a usable `java` is skipped
+/// instead of reported, so a stale value cannot shadow a working `PATH` entry
+/// (see the dangling-`JAVA_HOME` report in #5517).
+///
+/// The caller passes the environment explicitly so the tests stay hermetic.
+fn resolve_system_java_path(java_home: Option<&OsStr>, path_var: Option<&OsStr>) -> Option<PathBuf> {
+    if let Some(home) = java_home.filter(|value| !value.is_empty()) {
+        if let Some(java) = resolve_java_under_root(Path::new(home)) {
+            return Some(java);
+        }
+    }
+
+    let path_var = path_var.filter(|value| !value.is_empty())?;
+    std::env::split_paths(path_var)
+        .filter(|dir| !dir.as_os_str().is_empty())
         .map(|dir| dir.join(java_executable_name()))
         .find(|candidate| is_executable_file(candidate))
 }
 
+/// Report where the "system" Java runtime was looked for. Users who configured
+/// `JAVA_HOME`/`PATH` can still be running with the environment dbx was
+/// launched with, so name the exact values that were checked instead of only
+/// saying "not found".
+fn system_java_missing_error(java_home: Option<&OsStr>, path_var: Option<&OsStr>) -> String {
+    let java_home_detail = match java_home.filter(|value| !value.is_empty()) {
+        Some(value) => format!(
+            "JAVA_HOME={} does not contain {}",
+            value.to_string_lossy(),
+            Path::new(value).join("bin").join(java_executable_name()).display()
+        ),
+        None => "JAVA_HOME is not set".to_string(),
+    };
+    let path_detail = match path_var.filter(|value| !value.is_empty()) {
+        Some(value) => format!("no java in the {} PATH entries checked", std::env::split_paths(value).count()),
+        None => "PATH is not set".to_string(),
+    };
+    format!(
+        "System Java runtime was not found: {java_home_detail}; {path_detail}. \
+         Point JAVA_HOME at a JDK/JRE directory, add java to PATH, or choose a custom Java executable. \
+         dbx uses the environment it was started with, so restart dbx after changing environment variables."
+    )
+}
+
 fn is_executable_file(path: &Path) -> bool {
     if !path.is_file() {
         return false;