diff --git a/lib/install.ps1 b/lib/install.ps1
index 865d4ae5..40aeaad7 100644
--- a/lib/install.ps1
+++ b/lib/install.ps1
@@ -356,7 +356,7 @@ function install_msi($fname, $dir, $msi) {
 }
 
 function extract_msi($path, $to) {
-	$ok = run 'msiexec' @('/a', "$dir\$fname", '/qn', "TARGETDIR=`"$to`"")
+	$ok = run 'msiexec' @('/a', "`"$dir\$fname`"", '/qn', "TARGETDIR=`"$to`"")
 	if(!$ok) { abort "failed to extract files from $path" }
 }