Sony says its PlayStation Network service for video games was unusable from Sunday until Monday afternoon after being flooded by an online attack.
Sony Computer Entertainment spokesman Satoshi Nakajima said Monday the problems are fixed.
Separately, he said an American Airlines flight carrying Sony Online Entertainment President John Smedley from Dallas to San Diego was diverted to Phoenix about the same time as the attack.
An individual or group called Lizard Squad claimed through a Twitter account there might be explosives on the plane. The account also claimed responsibility for the attack on PlayStation Network.
Sony's network was compromised for about a month in 2011, including the personal data of 77 million accounts.
Sony says there was no breach of personal information in the latest incident.