Magento Open Source, 1.9.x
Notification Setup

You can specify how often your Message Inbox is updated, from one to twenty-four hours. If your store Admin has a secure URL, you must set the notifications to be delivered over HTTPS.

To configure Admin notifications:

1. On the Admin menu, select System > Configuration.
2. In the panel on the left, under Advanced, select System.
3. Click to expand the Notifications section, and do the following:
a. If your store Admin is running over a secure URL, set Use HTTPS to Get Feed to  “Yes.”
b. Set Update Frequency to one of the following:
  • 1 Hour
  • 2 Hours
  • 6 Hours
  • 12 Hours
  • 24 Hours
4. When complete, click the Save Config button.