Macintosh HD not showing in Startup Disk

[AlonCo]

So a few weeks ago I made a new partition to install El Capitan on, thinking that after testing it out I could just erase the default partition (being Macintosh HD - thought it was possible to do until now...).

A few minutes ago I just erased and (accidentally) ejected the Macintosh HD partition (it's backed up on external hard drive so no worries to the data) and so now what i'm trying to do is to startup back into Macintosh HD so I can erase the El Capitan partition and download the El Cap OS X into my default Mac HD partition.

Problem is, Macintosh HD is not showing on the startup disk panel in System Preferences.

So if someone knows how I can go back into my Macintosh HD partition,which is currently not showing on the Startup Disk even after restarting and holding the options key. That way I can erase the El Cap partition, install El Capitan OS X on the Mac HD and then everything will be fine...

Specifics: MacBook Pro (Retina, 15 inch, Early 2013)

Thanks so much!

 

[maflynn]

If you erased the Macintosh HD as you stated, then it won't show up in the start up pane because you cannot boot up the Mac from a blank drive.

 

[AlonCo]

If you erased the Macintosh HD as you stated, then it won't show up in the start up pane because you cannot boot up the Mac from a blank drive.

Well that's a bummer to hear. What can I do then? Is there a way to re-size the El Capitan partition? That way I can just make the Mac HD lets say 20gb and re-size the El Cap partition to 480gb.. But right now it's on 105gb and doesn't let me expand the size of it

 

[Mike in Kansas]

If you download the El Capitan installer to your existing El Cap partition, you can run the installer and install El Cap on the 'Macintosh HD' partition.

You should be able to expand the existing El Cap to the full size of the disk, basically wiping out the Macintosh HD partition. But Disk Utility may have some quirks in how it expands partitions; like, you may be able to expand Partition 1 to consume the whole SSD, but not the other way around.

Worst case, since you have your Macintosh HD backed up, you can just wipe the entire SSD and boot into Recovery mode, and download and install El Cap that way. Or make a bootable El Cap installer USB http://www.macworld.com/article/298...le-os-x-10-11-el-capitan-installer-drive.html
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