diff --git a/Launch-StudioBridge.bat b/Launch-StudioBridge.bat
index 78e4f4f..4520a70 100644
--- a/Launch-StudioBridge.bat
+++ b/Launch-StudioBridge.bat
@@ -16,13 +16,58 @@ set "ROOTDIR=%~dp0"
 REM Set the path to the portable-dist folder
 set "PORTABLE=%ROOTDIR%portable-dist"
 
-REM Check if StudioBridge.bat exists
-if not exist "%PORTABLE%\StudioBridge.bat" (
-        echo ERROR: Could not find portable-dist\StudioBridge.bat
-        echo Please make sure the portable-dist folder exists in:
-        echo   %PORTABLE%
+REM ---------------------------------------------------------------------------
+REM JRE auto-download (Temurin 21 LTS for Windows x64)
+REM ---------------------------------------------------------------------------
+set "JRE_DIR=%PORTABLE%\jre"
+set "JRE_EXE=%JRE_DIR%\bin\java.exe"
+set "JRE_ZIP=%TEMP%\temurin21-jre.zip"
+set "JRE_URL=https://github.com/adoptium/temurin21-binaries/releases/download/jdk-21.0.11%%2B10/OpenJDK21U-jre_x64_windows_hotspot_21.0.11_10.zip"
+set "JRE_FOLDER=jdk-21.0.11+10-jre"
+
+if not exist "%JRE_EXE%" (
+    echo [JRE] Java 21 runtime not found in portable-dist\jre\
+    echo [JRE] Downloading Temurin 21.0.11 LTS ^(~47 MB^)...
+    echo.
+
+    REM Use PowerShell to download the zip
+    powershell -NoProfile -Command "Invoke-WebRequest -Uri '%JRE_URL%' -OutFile '%JRE_ZIP%'" 2>nul
+    if not exist "%JRE_ZIP%" (
+        echo ERROR: Download failed. Please check your internet connection.
+        echo You can also manually place a Java 21 JRE at:
+        echo   %JRE_DIR%
         pause
         exit /b 1
+    )
+
+    echo [JRE] Extracting...
+
+    REM Extract zip then move the inner folder to jre\
+    powershell -NoProfile -Command ^
+        "Expand-Archive -Path '%JRE_ZIP%' -DestinationPath '%TEMP%\temurin21-extract' -Force; " ^
+        "Move-Item -Path '%TEMP%\temurin21-extract\%JRE_FOLDER%' -Destination '%JRE_DIR%' -Force; " ^
+        "Remove-Item '%TEMP%\temurin21-extract' -Recurse -Force -ErrorAction SilentlyContinue; " ^
+        "Remove-Item '%JRE_ZIP%' -Force -ErrorAction SilentlyContinue"
+
+    if not exist "%JRE_EXE%" (
+        echo ERROR: JRE extraction failed. Please manually place a Java 21 JRE at:
+        echo   %JRE_DIR%
+        pause
+        exit /b 1
+    )
+
+    echo [JRE] Java 21 runtime installed successfully.
+    echo.
+)
+REM ---------------------------------------------------------------------------
+
+REM Check if StudioBridge.bat exists
+if not exist "%PORTABLE%\StudioBridge.bat" (
+    echo ERROR: Could not find portable-dist\StudioBridge.bat
+    echo Please make sure the portable-dist folder exists in:
+    echo   %PORTABLE%
+    pause
+    exit /b 1
 )
 
 REM Change to the portable-dist directory