There are not many things that strike as much dread into the hearts of Mac clients as the feared mac flashing question mark folder in the screen on startup. That is a sign that your Mac can't discover its startup circle thus incapable for sure.
The explanations behind that run from the moderately amiable (you've recently fired up from an outer plate and unplugged it) to the more genuine (your Mac's hard drive has bombed disastrously). Whatever the reason, you'll discover counsel and fixes to help in the accompanying article. Peruse straightaway: mac folder question mark
We likewise have a total manual for fixing probably the most widely recognized Mac issues and How to begin a Mac in Safe Mode.