The university released documents that included Tressel's 2005-2006 personnel file, The Columbus Dispatch reported. Gene Smith, who became athletic director in 2005, began giving Tressel verbal performance reviews after that year.
The compliance review committee found that in the 2005-2006 season Tressel failed to report player violations of National Collegiate Athletic Association regulations. He was also found to have submitted late and incomplete paperwork on compliance.
The university also sent Tressel six warning letters between 2001 and 2005 about NCAA violations, the documents showed.
Tressel was forced to resign this year in the midst of a scandal over rule violations. Ohio State players sold memorabilia to the owner off a tattoo parlor, in some cases trading them for tattoos. Ohio State has submitted suggested penalties to the NCAA, including forfeiting the 2010 season, and university officials are scheduled to meet with the group's infractions committee Aug. 12.