Apple has issued an update to its OS X 10.8 Mountain Lion Developer Preview 3, but has left developers using the mid-2007 MacBook Pro unable to run the new build.
The new beta build, identified as 12A206J, was released to developers earlier this week, but Apple then told developers that the MacBook Pro model released in mid-2007 is unable to run the new build.
The pre-release build also has some other problems, with an error occurring when using Fast User Switching, and issues with the Mail and Twitter share menu.
Apple has also informed developers that QuickTime screen recordings can get corrupted when using computers with Nvidia graphics processing.
As in previous builds of the Mountain Lion preview, Notes cannot sync with iTunes, and Java applets don't always work in Safari.
The update is the second update this month for the Mountain Lion Developer Preview 3, which first became available to Developers in April.
It is expected that Apple will launch Mountain Lion at its Worldwide Developers Conference in June.