diff --git a/Telegram/build/prepare/prepare.py b/Telegram/build/prepare/prepare.py
index 6b2df1dec5..d7016c84bc 100644
--- a/Telegram/build/prepare/prepare.py
+++ b/Telegram/build/prepare/prepare.py
@@ -1625,7 +1625,14 @@ mac:
     cmake --install .
 win:
     cd qtbase
-    for /r %%i in (..\\..\\patches\\qtbase_%QT%\\*) do git apply %%i -v
+    setlocal enabledelayedexpansion
+    for /r %%i in (..\\..\\patches\\qtbase_%QT%\\*) do (
+        git apply %%i -v
+        if errorlevel 1 (
+            echo ERROR: Applying patch %%~nxi failed!
+            exit /b 1
+        )
+    )
     cd ..
 
     SET CONFIGURATIONS=-debug