Knowledgebase
How to change and configure the store email addresses in Magento
After you install Magento the store email addresses are example ones that you should change with functional ones if you want to be able to receive emails on these addresses. Log in to the admin panel of your Magento and go to System>Configuration>Store Email Addresses button in the General menu on the left. This will display a few panels on the right for each of the preconfigured store contacts (e.g. General Contact, Sales Representative, etc.). Expand the panels and you can change the name and email address associated with the contact.
By default, there's also a Contact Us functionality that's enabled by default. On the frontend there's a link in the footer that displays the contact us form that people can use to send you comments. To change the email address on which these comments are received, in the admin panel go to System>Configuration>Contacts button in the General menu on the left. Expand the Email Options panel on the right and use the drop-down menu for Send Emails To to select the contact email address that you want.
From the system settings you can select which of the store email addresses should be shown in the From field of transactional messages sent to customers. To change the email address associated with the welcome messages sent to new customers and the email confirmation messages (in case email verification is enabled) go to System>Configuration>Customer Configuration button in the Customers section on the left>Create New Account Options panel on the right, and edit the option Email Sender. On the same page expand the Password Options panel and use the drop-down menu Forgot and Remind Email Sender if you want to edit the email address shown in the From field of forgot your password messages. To change the email address shown in the From field of the various sales messages (e.g. order confirmation, shipment confirmation, etc.) go to System>Configuration>Sales Emails button in the Sales section on the left. Expand the panel that you want and edit the Sender option.
For more details and screenshots you can also read the tutorial on how to manage store email addresses in Magento.