I don't use a password on my system, I'm the only user and the only person with access.
But maybe this is what you want:To change the security levels and assign passwords user accounts
1. Log on as a user that will continue to have administrative privileges.
2. In Control Panel, double-click Users.
3. Click "Change an account".
4. Click the user account that you want to modify.
5. Click Change Account Type.
6. Click the type of account that you want to have for this user account.
7. Click the Change Account Type button.
8. To assign a password to this account, click "Create a password".
If not, wait for some input by someone who knows more about this than I