Apple has released a firmware update for the mid-2012 MacBook Air. The update attempts to resolve an issue that affects 64 GB and 128 GB models sold between June 2012 and June 2013. Apple says that the problem could lead to data loss. As this is a serious issue, the company has agreed to replace any affected drives that are unable to be updated. If the update installer detects that your drive is one of the models needing to be replaced, it will direct you to a page on Apple’s website that will allow you to obtain a replacement …
Apple also warns that if you have an affected drive, you should not attempt to install any additional software or updates. Instead, you should immediately backup your drive and look into your replacement options.
The firmware update is available on Apple’s support website or through the Software Update tab in the Mac App Store.
Apple has discovered that a small percentage of flash storage drives in these MacBook Air models have an issue that may result in data loss. This update tests your drive and, in the majority of cases, installs new firmware to resolve the issue. If your drive cannot be updated, Apple will replace it, free of charge
