diff --git a/filemanager.go b/filemanager.go
index becbac3e..fc67e4ba 100644
--- a/filemanager.go
+++ b/filemanager.go
@@ -292,6 +292,7 @@ func (m *FileManager) RegisterPermission(name string, value bool) error {
 		return nil
 	}
 
+	// Add the default value for this permission on the default user.
 	m.DefaultUser.Permissions[name] = value
 
 	for _, u := range m.Users {
@@ -299,6 +300,11 @@ func (m *FileManager) RegisterPermission(name string, value bool) error {
 			u.Permissions = map[string]bool{}
 		}
 
+		// Bypass the user if it is already defined.
+		if _, ok := u.Permissions[name]; ok {
+			continue
+		}
+
 		if u.Admin {
 			u.Permissions[name] = true
 		} else {