Zumbox, which had raised more than $30m from investors including the share registry company over a seven-year period.

Struggling US-based digital mail company Zumbox has announced that it is shutting down after seven years.

The company decided to call it quits despite receiving around $30m in investment from investors including Australia-based share registry company ComputerShare and investment fund Shelter Capital Partners.

Zumbox received a $10.6m investment from Australian share registry company ComputerShare in 2012, which was spent primarily on marketing and product expansion, but that cash injection was not enough to stave off growing competition from well-funded competitors…