HARTFORD, CT — After months of careful planning, Hartford Public Schools postponed the first day of school due to a ransomware attack.

Hartford Public Schools said in an email to parents and students that its technology “has been impacted by a ransomware virus making some of our platforms inaccessible.”

A ransomware virus is malware that locks the files and the attacker demands a ransom to restore access.

Around 1 a.m. this morning Hartford Public Schools said “Powerschool was one of the systems impacted and has been restored. Our online learning platforms, Google Classroom and SeeSaw, were not impacted by this issue.”

A second message sent around 5:30 a.m. said the ransomware attack impacted the transportation system, too, “preventing our ability to operate schools Tuesday.”

Hartford Public Schools has a staggered reopening process where Pre-K – Second Grade and Grades 6 and Grades 9 were supposed to start in-person learning Tuesday. Remote learning was also supposed to start for students and families that chose that option.

“Everyone at Hartford Public Schools was ready to welcome back our beautiful and capable students in person and remotely,” the email says.

There are approximately 17,000 students in the Hartford Public School system.

The first day of classes will take place Wednesday with adjusted classes in a staggered schedule for in-person learning.