Maintaining a connection with customers is essential to any business, no matter whether it’s a brick and mortar operation or an online enterprise. Companies frequently send newsletters and mailings with promotional offers, updates, and news. These efforts to acquire new business, or to retain existing customers, will be unfruitful if the emails sent are never opened. In fact, one of the most important measurements of email marketing is the open rate of mailings sent. Clearly, getting customers to open your emails is essential if you want to get your marketing messages across.