diff --git a/PageHowLS.nsh b/PageHowLS.nsh
index ffee8ef..17a1932 100644
--- a/PageHowLS.nsh
+++ b/PageHowLS.nsh
@@ -1,7 +1,7 @@
 ; How to install LS (for all users, or just for the current user)
 !ifndef PAGE_HOW_LS
 !define PAGE_HOW_LS
-	!include GetWindowsVersion.nsh
+	!include WinVer.nsh
 
 	Page custom ioHowLS
 	
@@ -10,10 +10,9 @@
 
 		; This option should not be visible on 9x based systems
 		; Check weather we're installing on a 9x or NT based system
-		Call GetWindowsVersion
-		Pop $R0
-		
-		StrCmp $R0 "9x" end
+		${IfNot} ${IsNT}
+			Abort
+		${EndIf}
 		
 		;If we get to this point we're not installing on a 9x based machine
 		!insertmacro MUI_HEADER_TEXT "$(TEXT_IO_TITLE_HOWLS)" "$(TEXT_IO_HOWLS)"
diff --git a/SectionCore.nsh b/SectionCore.nsh
index ffa9582..ef33c8d 100644
--- a/SectionCore.nsh
+++ b/SectionCore.nsh
@@ -6,7 +6,7 @@
 	!include BackupPersonal.nsh
 	!include Shell9x.nsh
 	!include ShellNT.nsh
-	!include GetWindowsVersion.nsh
+	!include WinVer.nsh
 	!include SectionsInclude.nsh
 	!include EnumLoginUsers.nsh
 
@@ -193,10 +193,7 @@
 		ReadINIStr $R0 "$PLUGINSDIR\ioHowLS.ini" "Field 4" "State" ;Field 4 is Don't set shell
 		${If} $R0 != 1
 			; Check whether we're installing on a 9x or NT based system
-			Call GetWindowsVersion
-			Pop $R0
-
-			${If} $R0 == "9x"
+			${IfNot} ${IsNT}
 				Call setShell9x
 			${Else}
 				Call setShellNT
diff --git a/Uninstaller.nsh b/Uninstaller.nsh
index 7a8ce3b..0321bd2 100644
--- a/Uninstaller.nsh
+++ b/Uninstaller.nsh
@@ -1,7 +1,7 @@
 !ifndef WRITE_UNINSTALLER
 !define WRITE_UNINSTALLER
 	!include uninstShell9x.nsh
-	!include GetWindowsVersion.nsh
+	!include WinVer.nsh
 	!include unStartExplorer.nsh
 	!include IndexOf.nsh
 	
@@ -25,10 +25,7 @@
 	SectionEnd
 	
 	Section Uninstall
-		Call un.GetWindowsVersion
-		Pop $R0
-	
-		${If} $R0 == "9x"
+		${IfNot} ${IsNT}
 			Call un.Shell9x
 		${Else}
 			;; Restore all the original values ;;