diff --git a/Telegram/build/prepare/prepare.py b/Telegram/build/prepare/prepare.py
index d60c818e3..fce761f88 100644
--- a/Telegram/build/prepare/prepare.py
+++ b/Telegram/build/prepare/prepare.py
@@ -855,9 +855,9 @@ win:
     SET MSYS2_PATH_TYPE=inherit
 
     if "%X8664%" equ "x64" (
-        SET "TARGET=x86_64-win64-vs17"
+        SET "TOOLCHAIN=x86_64-win64-vs17"
     ) else (
-        SET "TARGET=x86-win32-vs17"
+        SET "TOOLCHAIN=x86-win32-vs17"
     )
 
 depends:patches/build_libvpx_win.sh