KiwiRail says it will improve the systems at its national train control centre to prevent rail services grinding to a halt again.
The failure on Thursday of part of a power system at its Wellington-based control centre halted trains in Auckland, due to the loss of radio contact and signals.
Thousands of rush hour commuters were left stranded.
KiwiRail says it will review the control centre power system design. Chief executive Jim Quinn says the train control centre serves the whole country so whatever recommendations the review makes must be implemented quickly.
Mr Quinn says it's embarrassing and ironic an uninterruptible power supply unit failed.
The Auckland Mayor, Len Brown, says KiwiRail should be embarrassed, especially when hundreds of millions of dollars are being spent on upgrading the rail network.
Mr Brown says he will be asking Kiwirail about Auckland having its own rail control centre.
The Transport Accident Investigation Commission investigation into the cause of Thursday's failure is continuing.