Several students who sat NCEA digital exams last year have been wrongly failed.
The New Zealand Qualifications Authority (NZQA) has become aware of some results where no marks have been allocated.
The affected exams were in 2017 Digital pilot examinations in Classical Studies, English, and Media Studies, at Level 1 and Level 2.
Relevant schools were being contacted on Wednesday and NZQA is looking into how it occurred.
NZQA was reviewing any such results and, where marks should have been allocated, the students' record would be updated within the next few days, the spokeswoman said on Wednesday.
NZQA's quality assurance process included checking the marking of a randomly selected sample of digital examination entries, A NZQA spokeswoman said.
"These were check marked by a senior marker and no incomplete results were identified through this process."
NZQA had systems in place to ensure "no student is disadvantaged" and encouraged students who had an unexpected zero result in their 2017 Digital Pilot examinations to speak with their teachers in the first instance.
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