Troubleshooting your Mac when it acts up can be kind of daunting, but hang in there; I can give you a couple of steps to try before bringing the machine into us or Apple. These troubleshooting steps are the first things we try as technicians in order to fix an issue or make the system work.
If your machine is unresponsive, and pushing the power button doesn’t do anything, the first thing you want to do is an SMC reset. This is different for all machines, but you can Google the correct method for your Mac using the AppleCare name of your machine (the size, kind and generation it was made, e.g. Macbook Pro 13-inch Mid-2012).
For unibody MacBooks and MacBook Pros, press and hold the Shift+Option+Command keys, then press the power button (holding all four down for about ten seconds or so) and release all four buttons at the same time to do the SMC reset. Then try to start the machine. If it doesn’t work, you will need to bring the machine in to see us.
If your machine is having start-up troubles, won’t boot, or you get the gray screen, you can try what’s called a PRAM reset. This little trick is step number two that we try in the back. Just after hitting the power button on your machine, press and hold Option+Command+P+R keys. Hold all four keys down, and the machine will chime, then shut off, and start up again with another chime. It will continue to reboot itself until you let go of the keys (which you typically want to do on the third chime). This resets all of the startup settings which may have become corrupted or set incorrectly. If your computer starts, then you should be all set; otherwise you will need to bring the machine in for us to do more extensive diagnostics.
If you have issues after logging in, then the troubleshooting is a completely different animal — we now have to figure out where the problem lies. If you always have a program running when the problem occurs, try and reinstall the program or run software updates. A lot of the time, software updates will install bug fixes and solve minor problems.
Along the way, if you have seen error messages pop up or prompt you to send information to Apple, be sure to capture that info as it can be helpful for us to have if you need to bring your machine in for service. Between those and telling the check-in person what you have done to troubleshoot the issue, we’re much better prepared to repair your machine quickly!