diff --git a/MSIBuild/Makefile b/MSIBuild/Makefile
index 9e05710..4dfe6ac 100644
--- a/MSIBuild/Makefile
+++ b/MSIBuild/Makefile
@@ -91,7 +91,7 @@ WLANProfile	Component_	N			Component	1	Identifier		Component the profile is part
 
 All :: "$(LANG).$(PLAT).$(CFG).ActionText-2.idt"
 
-"En.$(PLAT).$(CFG).ActionText-2.idtx" : "Makefile" "..\..\..\include\MSIBuildCfg.mak"
+"en_US.$(PLAT).$(CFG).ActionText-2.idtx" : "Makefile" "..\..\..\include\MSIBuildCfg.mak"
 	-if exist $@ del /f /q $@
 	move /y << $@ > NUL
 Action	Description	Template
@@ -108,11 +108,11 @@ StartServicesExec	Starting services	Service: [1]
 InstallScheduledTasksExec	Installing scheduled tasks	Scheduled task: [1]
 <<NOKEEP
 
-!IF "$(LANG)" == "En"
-"En.$(PLAT).$(CFG).ActionText-2.idt" : "En.$(PLAT).$(CFG).ActionText-2.idtx"
+!IF "$(LANG)" == "en_US"
+"en_US.$(PLAT).$(CFG).ActionText-2.idt" : "en_US.$(PLAT).$(CFG).ActionText-2.idtx"
 	copy /y $** $@ > NUL
 !ELSE
-"$(LANG).$(PLAT).$(CFG).ActionText-2.idt" : "En.$(PLAT).$(CFG).ActionText-2.idtx" "..\locale\$(MSIBUILD_LANG_PO).po"
+"$(LANG).$(PLAT).$(CFG).ActionText-2.idt" : "en_US.$(PLAT).$(CFG).ActionText-2.idtx" "..\locale\$(LANG).po"
 	rcxgettext.exe idtp $@ $**
 !ENDIF
 
diff --git a/MSIBuild/build_all.bat b/MSIBuild/build_all.bat
index 16b8bc7..0ef78c1 100644
--- a/MSIBuild/build_all.bat
+++ b/MSIBuild/build_all.bat
@@ -1,9 +1,5 @@
 @echo off
-nmake.exe /ls All LANG=En CFG=Debug   PLAT=Win32
-nmake.exe /ls All LANG=Sl CFG=Debug   PLAT=Win32
-nmake.exe /ls All LANG=En CFG=Debug   PLAT=x64
-nmake.exe /ls All LANG=Sl CFG=Debug   PLAT=x64
-nmake.exe /ls All LANG=En CFG=Release PLAT=Win32
-nmake.exe /ls All LANG=Sl CFG=Release PLAT=Win32
-nmake.exe /ls All LANG=En CFG=Release PLAT=x64
-nmake.exe /ls All LANG=Sl CFG=Release PLAT=x64
+nmake.exe /ls All LANG=en_US CFG=Debug   PLAT=Win32
+nmake.exe /ls All LANG=en_US CFG=Debug   PLAT=x64
+nmake.exe /ls All LANG=en_US CFG=Release PLAT=Win32
+nmake.exe /ls All LANG=en_US CFG=Release PLAT=x64
diff --git a/MSIBuild/clean_all.bat b/MSIBuild/clean_all.bat
index b1ff08a..c2d1120 100644
--- a/MSIBuild/clean_all.bat
+++ b/MSIBuild/clean_all.bat
@@ -1,9 +1,5 @@
 @echo off
-nmake.exe /ls Clean LANG=En CFG=Debug   PLAT=Win32
-nmake.exe /ls Clean LANG=Sl CFG=Debug   PLAT=Win32
-nmake.exe /ls Clean LANG=En CFG=Debug   PLAT=x64
-nmake.exe /ls Clean LANG=Sl CFG=Debug   PLAT=x64
-nmake.exe /ls Clean LANG=En CFG=Release PLAT=Win32
-nmake.exe /ls Clean LANG=Sl CFG=Release PLAT=Win32
-nmake.exe /ls Clean LANG=En CFG=Release PLAT=x64
-nmake.exe /ls Clean LANG=Sl CFG=Release PLAT=x64
+nmake.exe /ls Clean LANG=en_US CFG=Debug   PLAT=Win32
+nmake.exe /ls Clean LANG=en_US CFG=Debug   PLAT=x64
+nmake.exe /ls Clean LANG=en_US CFG=Release PLAT=Win32
+nmake.exe /ls Clean LANG=en_US CFG=Release PLAT=x64