diff --git a/wp-admin/admin.php b/wp-admin/admin.php
index d84e3250c7..cd3770456a 100644
--- a/wp-admin/admin.php
+++ b/wp-admin/admin.php
@@ -103,7 +103,7 @@ if (isset($plugin_page)) {
 	}
 
 	// Allow plugins to define importers as well
-	if (! is_callable($wp_importers[$importer][2]))
+	if ( !isset($wp_importers) || !isset($wp_importers[$importer]) || ! is_callable($wp_importers[$importer][2]))
 	{
 		if (! file_exists(ABSPATH . "wp-admin/import/$importer.php"))
 		{