Major online retailer Kogan has copped a $310,800 fine for bombarding customers with spam.

An Australian Communications and Media Authority (ACMA) investigation found Kogan sent more than 42 million marketing emails to consumers from which they could not easily unsubscribe. Instead, Kogan required consumers to take additional steps setting a password and logging into a Kogan account.

ACMA found Kogan’s conduct breached the Spam Act, which requires commercial electronic messages to contain a functional unsubscribe facility.

"Kogan's breaches have affected millions of consumers," ACMA chair Nerida O'Loughlin said. "ACMA received complaints from a number of recipients of Kogan's email expressing their frustration and concern with Kogan's practices.

“Businesses must comply with the unsubscribe requirements in the spam rules. This investigation makes clear that businesses can't force customers to set a password and login to unsubscribe from receiving commercial messages."

ACMA has accepted a three-year court-enforceable undertaking from Kogan, requiring it to appoint an independent consultant to review its systems, processes and procedures, and to implement any recommendations from the review.

The undertaking also requires Kogan to train staff responsible for sending marketing messages and to regularly report back to the ACMA on actions taken in relation to consumer complaints.

Have you ever received email marketing messages from Kogan? Were you aware that there was a complaints process to detail with spam?