ChoKamir

Q: Black screen on startup after adjusting partions (Macbook)

Dear all,

 

This weekend I tried to resize my windows partition on my macbook. I succesfully reduced the size of the iOS partition. Rebooted in windows, and increased the size of the windows partition. For this the laptop had to restart (as the freed-up space was in front of the windows partition). The command tool processed the resize and restarted once completed.

 

However, upon this restart nothing happened... I hear the start-up chime, the backlight turns on, but that is it (nu cursor or anything). The screen stays black. Caps lock does not work (which I believe indicates it is not booting into an operating system).

 

I tried, all withouth success:

1) reboot several times

2) reset the SMC (I believe), by holding Shift+Control+Option+Power

3) reset PRAM (I believe), by holding Command+Option+P+R

4) go into the boot selection menu (by holding Option) or recovery mode (by holding Option+R)

 

Any other suggestions? What could be the problem. I seriously doubt it is a hardware problem, given it happened after running a software resize of partitions.

 

Cheers,

 

Chokamir

MacBook Air (13-inch, Early 2014), OS X El Capitan (10.11.6), Windows 7 installed via BootCamp

Posted on Sep 5, 2016 12:32 PM

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Q: Black screen on startup after adjusting partions (Macbook)

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  • Helpful answers

  • by Rysz,

    Rysz Rysz Sep 5, 2016 9:44 PM in response to ChoKamir
    Level 6 (19,670 points)
    iTunes
    Sep 5, 2016 9:44 PM in response to ChoKamir

    Partitions can be increased only in the clockwise direction. If your Windows partition was the second pie in Disk Utility, and you increased its size counterclockwise (or up), you likely erased your Mac partition.

     

    Start up in Internet Recovery mode: Command+Option+R

     

  • by ChoKamir,

    ChoKamir ChoKamir Sep 6, 2016 12:22 PM in response to Rysz
    Level 1 (9 points)
    Notebooks
    Sep 6, 2016 12:22 PM in response to Rysz

    Thank you for the suggestion! Unfortunately holding Command+Option+R does not work. The macbook still only shows a black screen.

     

    I indeed increased partitions counterclockwise. However, made sure I reduced the Mac partition beforehand and did not increase the windows partition beyond the free space. Hence it should not have overwritten the Mac partition. Nonetheless, I am afraid it has overwritten the MBR in a way that that macbook does not know what to do, and therefore cant boot beyond a black screen.

     

    Does a macbook have a something like a bios? How does it work? As I can't even seem to get into the boot mode selection, to select a USB to boot from. Or is there a way to make the macbook launch the iOS installer again (as you get when you buy the laptop), without formatting the harddisk?

     

    Thanks,

     

    Jelmer