Last week 2776 outpatients appointments were seen and 602 were cancelled.
DHB chief executive Dr Kevin Snee told Morning Report it would probably be next week before the IT systems were fully operational again.
"We're a very complex system and this has proved more complex to address than was first thought," Snee said. "We also have to careful in addressing the problem that when we stand up the system, it doesn't run into problems again."
Carrying out hospital procedures was more difficult than usual.
"We can't send, for example, lab tests electronically to the wards, it has to be done by paper and printing out ... everything is much slower than usual.
"Staff are getting into a routine now about how they manage things."
Snee said there had not been any further communication from whoever carried out the ransomware attack.
"I think our ability to respond to this as a country and an organisation is being tested - we're coping well so far and we're getting good help from our national and regional colleagues. I'm confident we'll continue to provide good service and I'm incredibly impressed by what work staff are doing."
Staff were having to search for the original referral.
''This means GPs refer patients to our services to see if we can pull out their referral letter which will have clinical information on it, which will be relevant to their visit.''
Lowry said patients could check on clinics on the DHB website, but if in doubt they should phone.
Extra staff would be needed to put the patient notes into the new IT system, Lowry said.
''There will be a whole lot of patient information which we will look to scan on to the electronic clinical record and other patient activity data, lab results etcetera that we will need to get into the system.''
It was all part of a recovery plan being worked on now, she said.
Pay errors
Snee said last week there were errors in pay which were corrected over a pay run the following day, and minor corrections were needed the day after that.
"As soon as we realised there was a problem we pulled out all the stops to sort it out.
"We had credit cards as a backup with $50 on them for people in particular hardship but none have been used.
Small errors were likely again, and staff had been given phone numbers call and speak to a manager in case of hardship, Snee said.
"I'm very confident that pay this week will be much more representative of the true pay ... if there's any errors we will rectify them immediately."
New Zealand Nurses Organisation kaiwhakahaere Kerri Nuku said there was some anxiety and frustration about pay errors.
"But I think hearing that when there had been errors, that they had been rectified relatively quickly, gives nurses and healthcare workers some reassurance ... but it doesn't stop the fear and anxiety.
"The nurses I've spoken to are just concerned and I think once they get through this week and see that the glitches may not be something that impacts on their lives, it might be a lot easier."
