diff --git a/development/cmake/build.bat b/development/cmake/build.bat
index f0b4dac2f7..f748ef9707 100755
--- a/development/cmake/build.bat
+++ b/development/cmake/build.bat
@@ -78,7 +78,7 @@ if "%1%" == "devel" (
 	REM Build solution to develop LyX
 	cmake %LYX_SOURCE%\development\cmake -G%USED_STUDIO% -DLYX_MERGE_FILES=0 -DLYX_NLS=1 -DLYX_DEBUG=1
 	REM needed when running lyx from the debugger
-	set LYX_DIR_20x="%LYX_SOURCE&"\lib
+	set LYX_DIR_20x=%LYX_SOURCE%\lib
 	start lyx.sln /build Debug
 )
 
@@ -86,7 +86,7 @@ if "%1%" == "install" (
 	REM Build solution to develop LyX
 	cmake %LYX_SOURCE%\development\cmake -G%USED_STUDIO% -DLYX_MERGE_FILES=1 -DLYX_INSTALL=1 -DLYX_RELEASE=1
 	REM needed when running lyx from the debugger
-	set LYX_DIR_20x="%LYX_SOURCE&"\lib
+	set LYX_DIR_20x=
 	start lyx.sln /build Debug
 )