The education ministry said Saturday that errors have taken place while processing the final exam reports of middle and high school students in the national education information system (NEIS), sparking massive confusion among applicants and schools. Due to miscalculated test rankings of some 20,000 high school students caused by source code errors, the ministry plans to reissue grade reports to all of the 1.9 million students attending 2,300 high schools nationwide, officials said. About 200 middle school students were also directly affected by the system malfunction, it said. \"We promptly corrected flaws that took place in the process of making final exam reports through the NEIS,\" the education ministry said in a release. The ministry said it will finish fixing the program and send revised reports by next week at the earliest. It said this is the first time that the education information system has generated such massive errors since South Korea computerized testing and grading systems in 1997. The NEIS was first adopted in March. With college admission processes set to begin next month, many applicants, parents and teachers expressed concerns over the security and accuracy of the system. \"We have repeatedly asked (the ministry) to improve the system during the semester because it has many problems, but they went unnoticed,\" said Kim Dong-seok, spokesman for the Korean Federation of Teachers\' Association. \"In light of this incident, the government should improve the system so that it can function correctly.\"