Microsoft is taking steps to ensure this scenario doesn't materialize again, according to de Haan.
De Haan didn't say how many people were affected by the outage and the company hasn't responded to a request for that information. The site that shows the status of its online services states that it lists problems that affect a "large number of customers."
He also didn't address the three straight days of maintenance work on Hotmail's Calendar component that began Monday and that the company warned could slow down the viewing and editing of calendars and trigger error messages. Users could also have experienced delays when syncing mail, contacts and calendar entries to their mail applications or phones, according to a status update.
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