Sony has started providing free software updates to more than half a million users around the world. The updates are meant to fix a problem that could cause Vaio laptops to overheat.

The company says that it had received 39 problem reports, 26 of which are in the United States, due to distortion of the shape of laptops and excessive heat. No injuries have been reported. Also, none of the complaints came from Japan.

The issues may affect 535,000 Vaio laptops worldwide. The problems may occur when the adapter is plugged in with nearly all its power used up. Sony has notified registered users by e-mail, offering a software application download to fix the flaw.

Sony has a history of product flaws. In 2006, the company recalled 9.6 million laptop batteries due to quality problems.