Penn State's admissions office received 310 incorrectly lowered SAT scores as a result of a scanning error that occurred during the grading of the October 2005 SAT test, Mary Adams, Penn State associate director of admissions, said Tuesday.

The processing error affected 4,000 students all over the world whose test scores had been reported by the College Board to more than 1,000 colleges and scholarship agencies.

The error also caused 600 test takers to receive higher grades than they were supposed to, said Brian O'Reilly, the College Board's executive director of SAT information services.

However, admissions offices will not find out which students received the higher scores. According to an e-mail message sent to Penn State's admissions office from the College Board, the board is contacting only those students who were supposed to receive a higher score.

"We will not penalize a student, especially this late in the process," O'Reilly said, pointing out that with application deadlines for many colleges approaching, most students seeking higher scores would not have an opportunity to retake the test.

"It would be unfairly penalizing them for a technical error that they had no control over," O'Reilly said.

Colleges that received incorrectly lowered scores received e-mail notifications of the error March 6, O'Reilly said. The e-mail notifications contained the names of each student who had his or her score lowered, the original score and the new score. Each student affected by the error was notified March 8 and told to go online to view the new score.

O'Reilly attributed the error to excessive moisture -- saying that heavy rainfall at the testing location or the storage site of the tests may have caused the answer sheets to expand. This compromised the accuracy of the scanner, O'Reilly said.

"The scanner is very precise, so it's aimed right at the bubbles," O'Reilly said. "If the test taker filled in very lightly or incompletely, then the scanner did not read that as an answer and treated that as if the student had not answered the question at all."

The incorrect SAT tests that Penn State received had scores that had to be changed by, in one case, as much as 300 points, though "the majority of students had point increases of 10 or 20 points," Adams said.

She said of the 310 incorrect score reports received, 259 had applied to Penn State, pointing out that some students send scores to colleges and never apply.

The admissions department has received calls from "a few" students, concerned that the scanning error could affect their chances of admission.

"We're telling them that we have the new scores, and we are looking again at our decision," said Adams, adding that once they became aware of the error, admissions officials immediately checked to see if the new scores would impact any decisions that had already been made.

"So far, we haven't changed a single decision based on the new SAT score report," Adams said.

Other Big Ten admissions offices have received incorrect score reports as a result of the scanning error.

The University of Michigan received 103 corrected SAT scores from the College Board, said Sally Lindsley, senior associate director in the office of undergraduate admissions. Of those, 83 had applied to the university, and most already had scores on file that were higher than the October 2005 test date. Officials in the department are re-reviewing 31 of the applications as a result of the new scores.

"The scores were not dramatically different -- many of them, it was only a 10-point increase," Lindsley said.

Ohio State University received 27 corrected SAT scores, said Stephanie Sanders, Ohio State's director of undergraduate admissions and first-year experience. Of those 27 students, 13 had actually applied to the university.

"Any time we get corrected information, we go back to the application and see if the new information affects the decision at all," Sanders said.