Web Outage Leaves Faculty, Students Without Access to Canvas for More Than 12 Hours

Canvas, Harvard’s main platform for classes, was nonoperational for more than 12 hours on Monday due to a widespread web outage, leaving students and professors unable to access class materials and submit assignments.

The global outage stemmed from Amazon Web Services, the world’s largest cloud infrastructure platform that supports roughly 30 percent of all cloud-based websites on the internet. It affected social media sites like Facebook, Snapchat, and the anonymous student site Sidechat, the cryptocurrency exchange Coinbase, and Delta and United Airlines.

According to Harvard University Information Technology, student-facing websites including Canvas, Adobe Creative Cloud, Panopto, Qualtrics, and Smartsheet were affected by the AWS crash.

AWS first reported the outage shortly after 3 a.m. on Monday morning, and access to Canvas was restored around 6:45 pm.

Before the site was restored, many Harvard professors postponed assignments that were due on Monday and emailed students readings and pages for the week. Economics 10: “Principles of Economics,” a popular introductory course among freshmen, granted students a 24-hour extension on the problem set that was due on Monday night, professor Jason Furman ’92 told The Crimson.

“I would not expect any measurable or persistent effects on the global economy as a result of this outage,” Furman wrote. “Unfortunately some of the resilience of the incredibly complicated and interconnected systems we rely on can only be sustained through trial and error. Fortunately they work the vast majority of the time in the vast majority of cases.”

HUIT sent a separate email to faculty on Monday evening with instructions on how to change the due date of an assignment on Canvas, post an announcement, and excuse students from late submissions.

Math 21A: “Multivariable Calculus” preceptor Adolfo A. Martin also granted students an extended deadline on their homework due during section on Monday.

“Since Canvas went down sometime last night, some students were unable to complete it. Fortunately, Gradescope is still functioning, so students should be able to meet the extended deadline tonight,” he said.

Thomas E. Nelligan ’27 said the outage mostly affected his ability to complete readings before classes.

“It’s been annoying, I’m not gonna lie,” Nelligan said. “I thought that I woke up from a nap and I figured it would be fixed, and it’s not. That’s kind of concerning. I think a lot of people have readings and stuff they usually do at night, like assignments due. And I think there’s obviously – it's not Harvard’s fault, per se – but there’s obviously a lack of clarity.”

Nelligan added that the blackout revealed Harvard’s dependence on Canvas and other sites to facilitate academics.

“It does reveal an overreliance on online systems, which is really frustrating,” he said. “I think it does make you think, ‘How did they do this before we had Canvas?’ They just made you turn things in in-person. It’s kind of goofy to say that, but it does feel like we’re over relying on technology for problems that we should have backups to.”

Summer R. Sinsley ’29 said two professors emailed slides and problem sets for the day, but being restricted from Canvas allowed her to “go out and explore the town.”

“I went to a grocery store and picked up some yummy snacks, and so it was kind of a blessing in disguise,” she said.

Emran Lakhlifi ’29, a student in Economics 10 and Math 21A, said that when he tried to access class materials on Canvas, all he could see was the site’s error screen.

“I was working on two math p-sets, and thank goodness I completed them before going to bed, because I woke up and hit that refresh button and I’m greeted by this broken spaceship,” he said.

Correction: October 21, 2025

A previous version of this article used the incorrect middle initial for Thomas E. Nelligan ’27.

—Staff writer Evan H.C. Epstein can be reached at evan.epstein@thecrimson.com. Follow him on X at @Evan_HC_Epstein.

—Staff writer Graham W. Lee can be reached at graham.lee@thecrimson.com. Follow him on X @grahamwonlee.