DoC Director-General Lou Sanson said it was expected the system would be fully operational by the middle of next year.
"Staff are still able to use the database to carry out regular work but delays in implementation mean they are currently unable to access the full operational benefits of the new system,'' Mr Sanson said in a statement.
"To date about 90 percent of the problems identified with the upgrade have been resolved and staff are starting to transfer onto the new system. The upgrade will provide a much better platform for managing conservation land and we are focused on making the full benefits available to all staff as soon as possible.''
But in a stinging independent report in February this year management consultants Deloitte said: "ineffective governance and management" of the project "has meant that a successful outcome had not been delivered".
While Linz were using the system, DoC wasn't and had been forced to spend the extra cash to get the system "to a point where it will meet their business needs".
Deloitte said the project wasn't well set up from the beginning and governance and project management controls "fell short of good practice".
"These issues became prevalent as the programme was heading towards the final stages of its implementation."
Deloitte acknowledged that both DoC and Linz and their staff were under pressure during the project which was also hampered by the Christchurch earthquakes.
In its own report on the project late last year, DoC said the project "has met the stated objectives".
Deloitte criticized DoC's closure report which "did not reflect the true situation at the time of closure. Deloitte noted DoC's report said the programme had been successfully delivered "when there were contrary views".
It also note that it heard comments blaming ICS for a number of the failures in the programme.
"However the Programme Manager was responsible for managing and overseeing the vendor (or should have been). This goes to effective management of the vendors and inadequate accountability being placed on the Programme Manager", Deloitte said.
"What is it with government screwing up IT projects?", Taxpayers Union executive director Jordan Williams asked.
"DoC officials need to be held accountable for this mismanagement. The Deloitte reports are damning of the mismanagement of the project. The public should have known about this a lot earlier."
Mr Williams said the DoC report "seems to skim over the clear failings of the project management".
"That closing report should have included the lessons learned from this cock up. It does nothing of the sort."
