How to protect critical user?

To Protect the critical user like uid=1 (admin), use Protect Critical Users

This module protects critical users from being deleted in the following ways:

- Catches user/*/delete requests to protect users 0 (anonymous), 1 (admin) and current user.
- Protects user 1 and current user from being deleted from user administration.
- Removes delete button from user edit form for user 1 and current user.

This module will not be upgraded to Drupal 7 because it looks like it will already protect critical users.

Note:Protect Critical Users is not compatible with User Delete module (ref. #507890).