In case you have forgot your Magento admin password and need to reset it then you can use the forgot password link provided in the login screen or you can directly reset it in the database.

On the “Forgot your password” screen enter admin user email address and click “Retrieve Password” button, an email will be sent with link to reset your password.

In Magento Enterprise Edition a security feature has been implemented which allows you to set the number of failed login attempts after which your account will get locked.

To make these security setting go to  Admin >> System > Configuration, click the Admin tab in the left column, and select the Security section.

It is advised to disable unused modules in Magento for website optimization. Also while troubleshooting issues we can temporarily disable module(s) to see which module(s) is/are causing the issues.

Let see how we can disable the modules in Magento:

1. Login to Magento admin and go to Admin >> System >> Configuration. On the left hand side click on the Advanced section under Advanced tab.

Customers can be added as well as deleted from Magento admin. To delete customers login to Magento Admin and in the menu select Customers >> Manage Customers.

This displays the customers listing grid. Now select the customers you want to delete by checking the checkbox in each customer row and then in the actions drop down select “Delete” and click the “Submit” button. Also you can click on the “Edit” link to open the customer edit screen; the edit page has a “Delete” button, click it to delete the customer.

If you are comfortable working with database then you may run queries using MySql client to delete the customer data but be sure to take a database backup before working on it so that you can restore it if anything goes wrong.