Mac os x boot caches updating
Once you hear the startup tone hold down the Shift key on your keyboard.When the grey Apple logo appears, release the Shift key.If you get an error message while installing mac OS Sierra saying that you don't have enough hard drive space, then restart your Mac and boot into safe mode.To do this, turn off your Mac and wait 10 seconds, the press the power button.Boot your Mac into Safe mode, then try installing mac OS Sierra again.It might also be worth switching from a Wi-Fi connection to a wired connection before you download and install.
But, since most do not do this very quickly, you might be waiting a while. The good news is that this problem is pretty easy to rectify, so you'll be back to listening to your favorite tunes in no time!To force-quit an item, click it in the Activity Monitor list, then click the X at the left of the toolbar, then confirm you want to force-quit. Open the Finder window, select 'Go' from the top menu and select 'Go to Folder'.In the text box that appears type /Library/Caches Remove the data from inside every folder.If you do experience any problems with mac OS Sierra, then don't worry – you're not alone, and we've collected solutions to the most common issues to help you get your Mac working just the way it should.If your Mac crashes or becomes unresponsive while installing mac OS Sierra, then there are a few things you can try to fix the problem.
First of all, try restarting your Mac to see if that helps.