Index: thunar-vfs/thunar-vfs-user.c
===================================================================
--- thunar-vfs/thunar-vfs-user.c	(revision 21175)
+++ thunar-vfs/thunar-vfs-user.c	(working copy)
@@ -586,6 +586,8 @@
 static void
 thunar_vfs_user_manager_init (ThunarVfsUserManager *manager)
 {
+  struct passwd *pw;
+
   manager->groups = g_hash_table_new_full (g_direct_hash, g_direct_equal, NULL, g_object_unref);
   manager->users = g_hash_table_new_full (g_direct_hash, g_direct_equal, NULL, g_object_unref);
 
@@ -599,6 +601,11 @@
   setpassent (TRUE);
 #endif
 
+  /* initialize groups */
+  pw = getpwuid (geteuid ());
+  if (G_LIKELY (pw != NULL))
+    initgroups (pw->pw_name, pw->pw_gid);
+
   /* start the flush timer */
   manager->flush_timer_id = g_timeout_add_full (G_PRIORITY_LOW, THUNAR_VFS_USER_MANAGER_FLUSH_INTERVAL,
                                                 thunar_vfs_user_manager_flush_timer, manager,