diff --git a/contrib/msi/build-msi-ie.sh b/contrib/msi/build-msi-ie.sh
index df6f968b..aa255e50 100644
--- a/contrib/msi/build-msi-ie.sh
+++ b/contrib/msi/build-msi-ie.sh
@@ -155,7 +155,7 @@ cat > wix.xml << EOF
 
     <Icon Id="icon.ico" SourceFile="riv.ico"/>
     <Property Id="ARPPRODUCTICON" Value="icon.ico" />
-    <Property Id="Script" Value="[SystemFolder]\\cscript.exe" />
+    <Property Id="Script" Value="%WINDIR%\\System32\\cscript.exe" />
 
     <Directory Id="TARGETDIR" Name="SourceDir">
       <Directory Id="DesktopFolder"  SourceName="Desktop"/>
@@ -260,8 +260,9 @@ cat > wix.xml << EOF
     <WixVariable Id="WixUILicenseRtf" Value="${PKGLICENSEFILE}" />
     <Property Id="WIXUI_EXITDIALOGOPTIONALCHECKBOXTEXT" Value="Launch RiV-mesh" />
     <CustomAction Id="LaunchApplication"
+      FileKey="[Script]"
       Impersonate="yes" 
-      ExeCommand='"[Script]" "[MeshInstallFolder]mesh-ui-ie.js"'
+      ExeCommand='"[MeshInstallFolder]mesh-ui-ie.js"'
       Return="asyncNoWait" />
 
     <!-- Step 3: Include the custom action -->