2012 macbook pro 3 beeps and will not boot up

If you face such a situation, the first thing you need to do is stay calm. This is usually a warning sign depicting an underlying problem with the system and it might occasionally be accompanied by other signals such as loud beeps, blinking question marks, or a prohibitory sign on the screen. Though it happens rarely, after Mac system software undergoes an update (likely to happen after a hard drive change or firmware update or OS upgrade, etc.), it might sometimes get stuck at a white screen before starting up.

After you hit the power on button, you hear the familiar start-up chime but post that, your Mac screen turns white or gray and shows no sign of progress. Picture this scenario - you get your Mac’s old hard drive replaced with a shiny new SSD but run into problems.

Such a situation usually requires repairing of Mac start-up disk with Disk Utility application. This article lists down common fixes users can apply to boot up Mac SSD that refuses to start-up. Mac SSD not Booting? Try 5 Fixes to Boot up Your Mac

2012 macbook pro 3 beeps and will not boot up