Apple is recalling some of the hard drives that shipped with the iMacs it released in May, as they carry a risk of failure.
The company said on Friday that "a very small number" of the Seagate 1TB drives that came in this year's 21.5-inch and 27-inch iMac all-in-one desktop computers "may fail under certain conditions". It did not explain what those conditions might be, but it said the drives would be replaced free of charge.
Other configurations, such as those with 2TB hard drives or 256GB solid-state drives, are not affected. Customers wishing to figure out whether their system uses a 1TB Seagate drive can enter the iMac's serial number on this page.
If the system uses one of the risky drives, the customer can have the drive replaced at an Apple retail store or an authorised service provider, or they can call Apple technical support. Data will need to be backed up before replacement, and original OS installation discs will be needed to reinstall the operating system, apps and backed-up data.
Apple will carry out replacements until 23 July 2012, the company said.