Holly Honderich is a news correspondent for the British Broadcasting Corporation.
More than 10 million customers of Rogers, a Canadian telecoms giant, were left without internet or wireless services in July. Regulators want to know what happened.
The consequences ranged from potentially dangerous to frustrating.
Emergency services were not accessible on many phones. One Ontario hospital had to divert cancer patients when emergency radiation treatments were affected by a communications problem.
Many businesses were unable to accept cash payments due to the disruption of banking services.
The Weeknd's fans were turned away from the Rogers Centre after he was forced to cancel a hometown tour stop.
The Canadian Radio-television and Telecommunications Commission was unable to receive calls.
Rogers, one of Canada's main telecom firms, is facing intense scrutiny from the federal government and the CRTC, which has ordered Rogers to explain in detail what caused the "unacceptable" shutdown.
Rogers CEO Tony Staffieri apologized to customers for the system failure and offered a five day service credit.
Questions remain about how a seemingly routine process left millions without crucial access to online services, and on Friday a Parliamentary committee said it would be studying the incident in meetings this month.
It has been said that expressing frustration with Canada's telecoms industry has been described as a national pastime.
Richard Leblanc is a professor of law, governance and ethics at York University.
Most of the country's telecom market is held by the firms.
Mr Leblanc said that they are beholden to three companies. They have a lot of authority.
Canada has strict foreign ownership rules for the industry.
Ben Klass, a PhD candidate at the School of Journalism and Communication, said that the government has supported industries like the airlines out of fear of foreign countries taking over.
Canada has a bit of a complex. We want to make sure we don't become a branch of the US.
Multiple studies show that Canadians pay some of the highest mobile phone and roaming rates in the world.
Canada's non-competitive telecoms market has allowed the Big Three to face few consequences for shoddy service.
"Rogers will make every change and investment needed to help ensure that a similar outage won't happen again, and will work with the industry to ensure certain essential services won't be interrupted by technical issues," Mr Staffieri said.
Mirko Bibic, Bell's top executive, said last week that the company takes its role in Canadians' communications networks very seriously and was investing billions in upgrades for a robust and resilient infrastructure.
Canada's large land mass and sparse population make it expensive for telecom companies to provide service.
Rogers has had a difficult time recently.
July was the second time in two years that the internet went down.
The company's cable and wireless networks crashed in the same fashion. Rogers blamed the failure on a software update from a supplier.
The family-owned business was hit with a public relations crisis in the months after.
Edward Rogers, the son of the late family matriarch, wanted to remove the then-chief executive because he was responsible for the firm's under performance.
The stage was set for a very public family feud when Mr Rogers was stopped by his mother and sisters.
A judge ruled in favour of Mr Rogers. He said that Mr Staffieri was among the most highly regarded and seasoned executives in the industry.
Rogers is trying to close a C$20 billion takeover of Shaw Communications, so the timing of the outage was bad.
Rogers is still committed to the merger, according to Mr Staffieri.
The federal government and the Competition Bureau Canada need to approve Rogers.
There are doubts as to whether the relevant authorities will put more power in the hands of one company.
Mr Klass said that it wouldn't help their cause.
It would have been worse had Shaw been taken over by Rogers, as the customer base would have been knocked offline.
The country is vulnerable to network crashes due to its large reliance on just three telecoms firms.
Canada is vulnerable to cyber- attacks because it relies on a few firms.
"We've put all our eggs in one basket, and that's now a target for threat actors," said Mr Leblanc.
He said that financial services, healthcare, and emergency services are dependent on two or three players.
hostile actors could do a lot more damage if the system failed.
Rogers has until Friday to provide a detailed account of the failure.
Industry experts are calling for a public investigation into how this most recent outage happened.
Mr Leblanc said that it couldn't happen behind closed doors. There needs to be a public inquiry where the politicians are hauled in front of the telcos. Accountability is needed.
The only thing Mr Leblanc can do is call the competitors.
He said someone would be installing his internet on Saturday. I went with him.