Days after admitting he signed a 2012 thank you letter to convicted sex offender Jeffrey Epstein, the president of the Massachusetts Institute of Technology is fighting for his job and pledging to rethink how the university accepts donations.

Behind closed doors Wednesday night at MIT’s first faculty meeting of the semester, L. Rafael Reif apologized to professors. In his prepared remarks posted to the university’s website, he said his administration’s actions have undermined MIT’s reputation, explaining that he signs many thank you letters every week and didn't recognize Epstein's name on one.

At issue, though, isn’t that letter but why MIT staffers seem to have ignored a ban against accepting Epstein's money.

Read more: After Taking Jeffrey Epstein’s Money, MIT And Harvard Reconsider 'Anonymous' Donations

Reif said MIT should develop a new set of principles to decide from which people the university will accept donations.

Despite Reif's apologies, at least one professor tells WGBH News the mood on campus is grim. The scandal, which has enveloped MIT's Media Lab, after it was revealed that the organization had taken more money from Epstein than school officials originally disclosed. Ito resigned shortly after the New Yorker broke the story, which also noted he tried to hide Epstein's donations by marking them as anonymous.