diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 0c3116b..1fab251 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -87,6 +87,14 @@ jobs:
       - name: Build exe
         run: python build_windows.py
 
+      - name: Unblock files (rimuovi MOTW pre-zip)
+        shell: pwsh
+        run: |
+          # Per ridurre l'incidenza del bug "Failed to resolve
+          # Python.Runtime.Loader.Initialize" causato da Mark of the Web.
+          Get-ChildItem -Path dist/MusicTools -Recurse -Include *.dll,*.exe,*.pyd `
+            | Unblock-File
+
       - name: Package -> zip
         shell: pwsh
         run: |
diff --git a/core/config.py b/core/config.py
index 4548bf1..2a51184 100644
--- a/core/config.py
+++ b/core/config.py
@@ -5,7 +5,7 @@ import os
 import sys
 from pathlib import Path
 
-VERSION = "v1.7.6"
+VERSION = "v1.7.7"
 
 
 APP_NAME = "MusicTools"
diff --git a/main.py b/main.py
index f7d21cb..5af6b11 100644
--- a/main.py
+++ b/main.py
@@ -11,20 +11,37 @@ from pathlib import Path
 # senza l'inizializzazione esplicita. Fix conferma:
 # https://github.com/pythonnet/pythonnet/issues/2178
 if sys.platform == "win32":
-    try:
-        # Punta pythonnet ai propri file runtime dentro al bundle PyInstaller.
-        if getattr(sys, "frozen", False):
+    # ============================================================
+    # Fix Windows: rimuovi Mark of the Web (MOTW) dalle DLL bundled.
+    # Quando l'utente scarica il .zip dal browser, Windows aggiunge
+    # uno stream NTFS Zone.Identifier a TUTTI i file estratti.
+    # .NET Framework 4.x rifiuta silenziosamente di risolvere i
+    # symbol export degli assembly managed con MOTW -> il loader
+    # netfx di pythonnet fallisce con "Failed to resolve
+    # Python.Runtime.Loader.Initialize".
+    # Soluzione: cancelliamo lo stream :Zone.Identifier da ogni
+    # .dll/.exe del bundle al primo avvio (operazione idempotente
+    # e sicura: l'utente ha gia eseguito l'exe esplicitamente).
+    # Vedi: https://github.com/r0x0r/pywebview/issues/1215
+    # ============================================================
+    if getattr(sys, "frozen", False):
+        try:
+            import ctypes
+            _kernel32 = ctypes.windll.kernel32
             _bundle = Path(sys._MEIPASS)  # type: ignore[attr-defined]
-            _rt = _bundle / "pythonnet" / "runtime"
-            if _rt.exists():
-                os.environ["PYTHONNET_RUNTIME"] = "netfx"
-                os.environ["PYTHONNET_PYDLL"] = sys.executable
+            for _f in _bundle.rglob("*"):
+                if _f.suffix.lower() in (".dll", ".exe", ".pyd"):
+                    _kernel32.DeleteFileW(f"{_f}:Zone.Identifier")
+        except Exception as _e:
+            print(f"[bootstrap] MOTW cleanup failed: {_e}")
+
+    try:
+        if getattr(sys, "frozen", False):
+            os.environ["PYTHONNET_RUNTIME"] = "netfx"
         from pythonnet import load as _pythonnet_load
         _pythonnet_load("netfx")
         import clr  # noqa: F401  - inizializza il loader
     except Exception as _e:
-        # Se il preload fallisce, lasciamo che webview tenti comunque:
-        # l'errore originale verra' mostrato con stack trace.
         print(f"[bootstrap] preload pythonnet failed: {_e}")
 
 import webview
diff --git a/requirements.txt b/requirements.txt
index 41a9779..0fd41eb 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -5,4 +5,5 @@ mutagen>=1.47.0
 pyobjc-core>=10.0 ; sys_platform == "darwin"
 pyobjc-framework-Cocoa>=10.0 ; sys_platform == "darwin"
 pyobjc-framework-WebKit>=10.0 ; sys_platform == "darwin"
-pythonnet==3.0.3 ; sys_platform == "win32"
+pythonnet==3.0.5 ; sys_platform == "win32"
+clr-loader==0.2.7.post0 ; sys_platform == "win32"