Columbia University, where a former financial aid official is under criminal investigation for monetary ties to lenders, has agreed to pay a $1.1 million fine, adopt a conduct code, and let Attorney General Cuomo monitor the college for the next five years, Mr. Cuomo said yesterday.

Separately, the head of the 12,000-member National Association of Student Financial Aid Administrators, Dallas Martin, said the association would follow Mr. Cuomo’s conduct code, which bans private lenders from giving trips or gifts to aid officials.

Mr. Cuomo said his probe of the $85 billion student loan business has exposed campuses where officials owned stock in lending companies they were touting as “preferred” to students.

Mr. Martin conceded that a lot of people in the association have “been close to the line” and said he was sorry for initially questioning the propriety of Mr. Cuomo’s inquiry.

“I was pretty defensive and was fairly critical of the attorney general’s actions at that point. Today I want to apologize to him, as I’ve done previously, but personally to say that I was wrong,” he said.

For the next five years, aides from Mr. Cuomo’s office will attend conferences of the association to monitor its activities, they said.

Columbia, which fired David Charlow, an associate dean being investigated in connection with the probe, denied any wrongdoing.