Windows – Create a new partition after Bootcamp

There is no need to delete the CoreStorage Logical Volume Group. Just resize it:

1. Have a backup!

2. Reboot into Internet Recovery Mode (hold Option-Command-R) as the machine is restarting). You'll eventually be presented with a Max OS X Utilities window.

   

3. In the menu bar along the top of the screen, click Utilities -> Terminal.

   

4. At the prompt, enter diskutil cs list and you should get output similar to the following.

   CoreStorage logical volume groups (1 found)
   |
   +-- Logical Volume Group 9B4FB14F-DA7D-46EF-BBB9-FD99166C1E2F
       =========================================================
       Name:         Macintosh HD
       Status:       Online
       Size:         920186970112 B (920.2 GB)
       Free Space:   49152 B (49.2 KB)
   |
   +-< Physical Volume DE3C1DD4-3EA5-4484-AE40-C8BD60AD5F75
   |   ----------------------------------------------------
   |   Index:    0
   |   Disk:     disk0s2
   |   Status:   Online
   |   Size:     120988852224 B (121.0 GB)
   |
   +-< Physical Volume E1C56E99-3ED2-437F-AED0-A454FCC4E983
   |   ----------------------------------------------------
   |   Index:    1
   |   Disk:     disk1s2
   |   Status:   Online
   |   Size:     799198117888 B (799.2 GB)
   |
   +-> Logical Volume Family D824D426-8315-405A-A7CD-5B62E549FBAE
       ----------------------------------------------------------
       Encryption Status:       Unlocked
       Encryption Type:         None
       Conversion Status:       NoConversion
       Conversion Direction:    -none-
       Has Encrypted Extents:   No
       Fully Secure:            No
       Passphrase Required:     No
       |
       +-> Logical Volume AC1A071B-63D0-488F-AFFF-D296E446FE6B
           ---------------------------------------------------
           Disk:                  disk2
           Status:                Online
           Size (Total):          914000052224 B (914.0 GB)
           Conversion Progress:   -none-
           Revertible:            No
           LV Name:               Macintosh HD
           Volume Name:           Macintosh HD
           Content Hint:          Apple_HFS`
   

5. Copy the Logical Volume (LV) alphanumeric UUID of your CoreStorage volume. The LVUUID should be the fourth (the fifth if you have a Fusion Drive) listed. In the above example the alphanumeric is:
   AC1A071B-63D0-488F-AFFF-D296E446FE6B

6. Run the following command:

   diskutil cs resizeStack LVUUID partsize  
   

   According to the number found above it would be:

   diskutil cs resizeStack AC1A071B-63D0-488F-AFFF-D296E446FE6B 0g  
   

   This will expand your CoreStorage volume to full 1.24 TB

7. Quit Terminal.app and start Disk Utility and verify the expanded volume.

More people have problems with BootCamp trying to partition manually than any other way. This is what I would do:

1. Boot into recovery mode.
2. Get into disk utility
3. Delete the partition you created for Windows
4. Expand your Mac partition all the way into the available space
5. Now (assuming you already have the BootCamp media created) Run the BootCamp.app and follow the prompts
6. Part of the process will present you with a graphical representation of your disk and allow you to set as much space as you want for both the Mac and Windows partition.

The thing you have to learn (or un-learn as the case may be) coming from Linux or Windows is that the first thing you should do is nothing. Let the App and/or Operating System do it's thing the way it wants to. Which means things like, "just plug it in," "follow the prompts in the app," or as a last resort read the (usually brief) instructions in the app or on Apple's support web site.

I've been supporting Macs and PCs for 20+ years and it is a whole different mindset. Yes you can tinker, it's just a different method. What you did is not wrong, it just adds unnecessary complications making it necessary to then work around Apple's work-around that they build into BootCamp so you would not have to do all the partitioning manually.