Some devices failed to recognize that northwestern communities in the Central Time Zone are permanently observing Daylight Saving Time.
Some residents reported on Sunday that the time on their smartphones, computers, and vehicle clocks fell back one hour, as had been the past practice.
It required a manual reset to get the correct time.
Some companies and businesses were also correcting operating systems that are time-sensitive.
The Ontario government allowed area communities to remain on the same time as Manitoba, which is also staying on Daylight Saving Time.
The decision also puts Central Time Zone communities on the same time as the rest of Ontario and Quebec until next March.
