How to Disable Magento Newsletter Module
How to Disable/Enable Magento Newsletter Module
In Magento customers can subscribe to your newsletter. The newsletter subscription function is enabled by default. Customers can sign up for the newsletter while creating an account, registered customers can subscribe from their account settings, and guests can subscribe from the Newsletter block displayed in one of the columns. If, however, you don't want to send newsletters and you want to disable this function you can do this from the admin panel of your Magento.
Disable Magento Newsletter
To do this, log in to the admin panel of your Magento and go to
System menu -> Configuration -> Advanced button under the Advanced section on the left. -> find Mage_Newsletter drop-down menu to Disable -> Click Save
Don't forget to click on the Save Config button in the upper right corner. This will automatically remove the newsletter subscription options from the front-end of your site.
Enable Magento Newsletter
If you want to enable the newsletter function again, just set the Mage_Newsletter drop-down menu to Enable.
System menu -> Configuration -> Advanced button under the Advanced section on the left. -> find Mage_Newsletter drop-down menu to Enable -> Click Save
Now you can control your newsletters