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Canada’s main stock index will be open for business on Monday, after an unusual outage prompted the S&P/TSX to shut down early on Friday.

An “internal technical issue” prompted the TMX group to shut down its exchanges in Toronto and Montreal at 3 p.m. Friday, with the last data reading showing the S&P/TSX up 31.34 points at 15,668.93.

In a statement Saturday, TMX says the outage was caused by a “hardware failure in a central storage appliance.”

The company says it began fixing the problem Friday afternoon by replacing the defective module and verifying the integrity of the affected data.

It says that due to the timing of the incident, it was impossible to implement disaster recovery systems in time to reopen on Friday.

TMX says the incident was not the result of a cyberattack.

“We apologize to all of our valued clients across Canada’s capital markets and around the world,” TMX CEO Lou Eccleston said in the Saturday statement.

“TMX is committed to applying the lessons learned from this incident to help us prevent such issues from recurring in the future.”