Technicians failed to install six bytes of the software, developed by Shenzhen Sea Skyland Technologies Co. Ltd, resulting in the failure to collate the results of question 39 in a 300-score section of the college entrance exam, said Cheng Yi, director of the Anhui Education Department.

The failure affected 260,000 liberal arts candidates who sat the exam on June 7 and 8 in Anhui.

The error was found on Tuesday when the Recruitment and Exam Institute of the Anhui Education Department organized technicians to check the results of the exam as candidates had complained there was a big gap between their marks and what they believed they should have got.

The scores of the college candidates were released on Monday in Anhui.

Candidates in Anhui got marks ranging from zero to 28 in question 39, Cheng said.

All the marks of the candidates affected had been recalculated and released on Wednesday. The admission mark lines for universities were also readjusted.

The education department said they also conducted checks on other subjects, but found no abnormal results.

The date for candidates to submit their college choices has been postponed until July 1 in Anhui.

The college entrance exam to a great extent decides the fate of candidates as many regard it as an opportunity to change their lives.

This year, around 9.5 million people sat the exam, which has a maximum score of 750 in all the sections.

Some students and parents still expressed concern after the marks were amended.

A parent at the Anhui Recruit Office said his child left home two days ago because of his unsatisfactory exam result and was yet to return.

A candidate in Hefei, capital of Anhui, said, "Some exam workers seem to regard this as a trifling matter, but this exam can decide our fate. It's a detestable thing."

Shenzhen Sea Skyland Technologies Co. Ltd was established in 1997 in Shenzhen, south China's Guangdong Province. Its exam paper scoring software has serve 5.1 million students by 2006.

However, the company declined an interview by Xinhua by saying "the executives are all on business trips" and their mobile phone numbers "can not be disclosed".

Senior officials with the Anhui Education Department admitted that "relevant exam workers are also to blame because they failed to find and correct the error in time".

It is the second year that Anhui has used the software of the Shenzhen company to score papers of college entrance exams.

The Anhui government has ordered education authorities to apologize and explain to affected college candidates and their parents.