Air Canada says it has resolved a computer issue that caused problems at airports that resulted in some flight delays.
The Montreal-based airline had warned in a travel advisory that it was having trouble with completing bookings and passenger check-ins.
Details of the outage weren't immediately available.
Several Air Canada flights departing from its hub at Pearson International Airport in Toronto and Montreal's Trudeau International Airport were cancelled.
On its website, the airline said some of the flights were affected by adverse weather including freezing rain.
The airline has been fielding complaints on Twitter from passengers who missed flights due to the outage.