Apple has released an update for 15- and 17-inch MacBook Pro systems released in mid-2010, which addresses a problem that could cause freezes and hangs during use, and more notably during start-up. The prevalence of this problem is rare, but has affected a few systems.
In addition to the freezes and hangs, the update addresses compatibility issues with external displays.
In order to install the update, you will need to have your external power supply attached and should expect a gray screen with a status bar appear when the system reboots. It is important that you do not interrupt this … Read more