diff --git a/usermin/upgrade.cgi b/usermin/upgrade.cgi
index 46b0ba833..c20ba0582 100755
--- a/usermin/upgrade.cgi
+++ b/usermin/upgrade.cgi
@@ -15,6 +15,17 @@ else {
 
 &ui_print_unbuffered_header(undef, $in{'install'} ? $text{'upgrade_title2'} : $text{'upgrade_title'}, "");
 
+# Do we have an install dir?
+my $indir = $in{'dir'};
+if (!$indir) {
+	my $install_dir = "$config_directory/install-dir";
+	if (-e $install_dir) {
+		$indir = &read_file_contents($install_dir);
+		$indir = &trim($indir);
+		$indir = undef if (!-d $indir);
+		}
+	}
+
 if ($in{'source'} == 0) {
 	# from local file
 	&error_setup(&text('upgrade_err1', $in{'file'}));
@@ -245,7 +256,7 @@ else {
 		}
 	else {
 		# Upgrading .. work out where to extract
-		if ($in{'dir'}) {
+		if ($indir) {
 			# Since we are currently installed in a fixed directory,
 			# just extract to a temporary location
 			$extract = &transname();
@@ -265,7 +276,7 @@ else {
 		$ENV{'config_dir'} = $config{'usermin_dir'};
 		$ENV{'webmin_upgrade'} = 1;
 		$ENV{'autothird'} = 1;
-		$setup = $in{'dir'} ? "./setup.sh '$in{'dir'}'" : "./setup.sh";
+		$setup = $indir ? "./setup.sh '$indir'" : "./setup.sh";
 		if ($in{'delete'}) {
 			$ENV{'deletedold'} = 1;
 			$cmd = "(cd $extract/usermin-$version && $setup && rm -rf \"$miniserv{'root'}\")";
@@ -278,7 +289,7 @@ else {
 	print "<pre>";
 	&proc::safe_process_exec($cmd, 0, 0, STDOUT, undef, 1);
 	print "</pre>";
-	if ($in{'dir'}) {
+	if ($indir) {
 		# Can delete the temporary source directory
 		system("rm -rf \"$extract\"");
 		}
diff --git a/webmin/upgrade.cgi b/webmin/upgrade.cgi
index 6bf4b3bfa..f4f31d787 100755
--- a/webmin/upgrade.cgi
+++ b/webmin/upgrade.cgi
@@ -11,6 +11,17 @@ $| = 1;
 $theme_no_table = 1;
 &ui_print_header(undef, $text{'upgrade_title'}, "");
 
+# Do we have an install dir?
+my $indir = $in{'dir'};
+if (!$indir) {
+	my $install_dir = "$config_directory/install-dir";
+	if (-e $install_dir) {
+		$indir = &read_file_contents($install_dir);
+		$indir = &trim($indir);
+		$indir = undef if (!-d $indir);
+		}
+	}
+
 # Save this CGI from being killed by the upgrade
 $SIG{'TERM'} = 'IGNORE';
 
@@ -361,7 +372,7 @@ elsif ($in{'mode'} eq 'solaris-pkg' || $in{'mode'} eq 'sun-pkg') {
 		$dir = $1;
 		}
 
-	$setup = $in{'dir'} ? "./setup.sh '$in{'dir'}'" : "./setup.sh";
+	$setup = $indir ? "./setup.sh '$indir'" : "./setup.sh";
 	print "Package Directory: $dir<br>";
 	print  "cd $dir && ./setup.sh<br>";
 	&proc::safe_process_exec(
@@ -439,7 +450,7 @@ else {
 		}
 
 	# Work out where to extract
-	if ($in{'dir'}) {
+	if ($indir) {
 		# Since we are currently installed in a fixed directory,
 		# just extract to a temporary location
 		$extract = &transname();
@@ -498,7 +509,7 @@ else {
 	$ENV{'deletedold'} = 1 if ($in{'delete'});
 	print "<p>",$text{'upgrade_setup'},"<p>\n";
 	print "<pre>";
-	$setup = $in{'dir'} ? "./setup.sh '$in{'dir'}'" : "./setup.sh";
+	$setup = $indir ? "./setup.sh '$indir'" : "./setup.sh";
 	&proc::safe_process_exec(
 		"cd $extract/webmin-$version && $setup", 0, 0,
 		STDOUT, undef, 1, 1);
@@ -508,7 +519,7 @@ else {
 			# Can delete the old root directory
 			system("rm -rf ".quotemeta($root_directory));
 			}
-		elsif ($in{'dir'}) {
+		elsif ($indir) {
 			# Can delete the temporary source directory
 			system("rm -rf ".quotemeta($extract));
 			}