The acting Education Secretary says software company Talent2 has committed a significant privacy breach by emailing advice on payroll problems to the wrong schools.
Peter Hughes says a Talent2 staff member made the mistake and about 1600 schools are involved.
Mr Hughes says 3400 transactions were emailed to school pay administrators on Tuesday detailing the names and Ministry of Education numbers for staff at another school instead of their own.
He says at least 40 transactions contained extra information such as dollar amounts for advance payments or overpayments.
Peter Hughes says the information has not been made public and he trusts school pay administrators to delete it with discretion.
He says he apologises to staff and has asked Talent2 to provide a report by the end of this week on how the Australian-based company will prevent this happening again.