diff --git a/phpBB/install/database_update.php b/phpBB/install/database_update.php
index 377e38c423..7b20404cf2 100644
--- a/phpBB/install/database_update.php
+++ b/phpBB/install/database_update.php
@@ -2749,6 +2749,33 @@ function change_database_data(&$no_updates, $version)
 				$config->set('site_home_url', '');
 				$config->set('site_home_text', '');
 			}
+			
+			
+			// ticket/10601: Make inbox default. Add basename to ucp's pm category
+			// Check if this was already applied
+				$sql = 'SELECT module_id, module_basename, parent_id, left_id, right_id 
+						FROM ' . MODULES_TABLE . '
+						WHERE 
+						module_basename = \'ucp_pm\'
+						ORDER BY module_id';
+				$result = $db->sql_query_limit($sql, 1);
+
+				if ($row = $db->sql_fetchrow($result))
+				{
+					// Checking if this is not a category
+					if ($row['left_id'] === $row['right_id'] - 1)
+					{
+						// This update is still not applied. Applying it
+						
+						$sql = 'UPDATE ' . MODULES_TABLE . '
+							SET module_basename = \'ucp_pm\'
+							WHERE  module_id = ' . (int)$row['parent_id'];
+						
+						_sql($sql, $errored, $error_ary);
+					
+					}
+				}
+				$db->sql_freeresult($result);
 
 		break;
 	}