An administrative error was to blame for an e-mail sent out by the University of California San Diego telling about 28,000 previously denied applicants that they were accepted to the Southern California school, The Los Angeles Times reported.
Earlier in the month, the students got e-mail notices saying they were denied admission.
But on Monday, someone accidentally sent out a second e-mail — this one an acceptance letter — to all 47,000 applicants, Admissions Director Mae Brown told the Times.
It was intended for just the roughly 18,000 that got in.
"I take full responsibility for the error," said Brown. "We recognized the incredible pain receiving this false encouragement caused. It was not our intent."
One parent interviewed by the Times called the erroneous acceptance his daughter received a "colossal screw-up."