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Pete, Engineer
Category: Phone Systems
Satisfied Customers: 17397
Experience:  Over 16 years experience installing and repairing electronics.
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FOR PETE ONLY. Please give me instructions on how to

This answer was rated:

FOR PETE ONLY. Please give me instructions on how to reinstall Sierra. Also read the statistics for All Processes on the Activity Monitor which I detailed in my previous question/thread. After reading the statistics do you still think I should reinstall Sierra?

I am Pete, and I'll be happy to assist with your question today.

Hi Jeff, everything looks normal in Activity Monitor.

It would be worth just checking it again, immediately after a reboot, as soon as is practicable.

If there is still no unusually high activity then you can try reinstalling the Sierra OS:

To reinstall macOS, you must be connected to the Internet.

  1. In the menu bar, choose Apple menu > Restart. As your Mac restarts, hold down the Command and R keys until the macOS Utilities window appears.

  2. Select Disk Utility, then click Continue.

  3. Select your startup disk on the left, then click Erase.

  4. Click the Format pop-up menu, choose Mac OS Extended, enter a name, then click Erase.

    Important: Erasing the disk removes all the information from the disk. Be sure to back up the information you want to keep to an external device.

  5. After the disk is erased, choose Disk Utility > Quit Disk Utility.

  6. Select Reinstall macOS, click Continue, then follow the onscreen instructions.

Customer: replied 13 days ago.
As I recall, after you press the command & R a menu comes up with one option being to reinstall the OS. What happens if you click that WITHOUT FIRST erasing the startup disk?

If there are any corrupt files in the start up disk then they will not be replaced if it is not erased first.

Pete and other Phone Systems Specialists are ready to help you
Customer: replied 13 days ago.
If I erase the startup disk does that mean I will lose ALL my files & apps (including updates I've purchased since upgrading to Sierra?
Customer: replied 11 days ago.
Pete please reply to my last question so I can rate you. We've pretty much exhausted this subject. I just want to know if I erase the startup disk will I lose any files or apps?
Customer: replied 9 days ago.
I'm going to rate you even though you did not reply to my last question. Would appreciate you doing so after I rate you. You have put a lot of time and expertise into my computer freezing problem and I thank you for this.

Hi Jeff, sorry for the delay in getting back to you, I did not see any notification of your replies.

The answer is.... it depends.

The startup disc should only be for your MacOS software and nothing else, so by erasing it you will only lose the operating system.

However if you have installed files and apps onto the startup partition (not best practice) then you will lose anything that is saved on it.

So it depends on where you have saved your files and apps - certainly make a backup of everything before performing this.

Thanks very much for the rating!