I did everything as outlined but the changes will not save. Here is the outcome:
Last login: Thu Oct 22 17:58:22 on ttys001
MEPro:~ ME$ sudo gdisk /dev/rdisk0
Password:
GPT fdisk (gdisk) version 1.0.1
Warning: Devices opened with shared lock will not have their
partition table automatically reloaded!
NOTE: Write test failed with error number 1. It will be impossible to save
changes to this disk's partition table!
You may need to deactivate System Integrity Protection to use this program. See
https://www.quora.com/How-do-I-turn-off-the-rootless-in-OS-X-El-Capitan-10-11
for more information.
Partition table scan:
MBR: hybrid
BSD: not present
APM: not present
GPT: present
Found valid GPT with hybrid MBR; using GPT.
Command (? for help): P
Disk /dev/rdisk0: 977105060 sectors, 465.9 GiB
Logical sector size: 512 bytes
Disk identifier (GUID): 415DC92E-1F12-4519-AA28-3433684C2B4D
Partition table holds up to 128 entries
First usable sector is 34, last usable sector is 977105026
Partitions will be aligned on 8-sector boundaries
Total free space is 290253009 sectors (138.4 GiB)
Number Start (sector) End (sector) Size Code Name
1 40 409639 200.0 MiB EF00 EFI System Partition
2 409640 197302423 93.9 GiB AF00 MACOS
3 197302424 198571959 619.9 MiB AB00 Recovery HD
4 488824832 977104895 232.8 GiB 0700 BOOTCAMP
Command (? for help): D
Partition number (1-4): 4
Command (? for help): N
Partition number (4-128, default 4): 4
First sector (34-977105026, default = 198571960) or {+-}size{KMGTP}: 198572032
Last sector (198572032-977105026, default = 977105026) or {+-}size{KMGTP}: +778532857
Current type is 'Apple HFS/HFS+'
Hex code or GUID (L to show codes, Enter = AF00): 0700
Changed type of partition to 'Microsoft basic data'
Command (? for help): P
Disk /dev/rdisk0: 977105060 sectors, 465.9 GiB
Logical sector size: 512 bytes
Disk identifier (GUID): 415DC92E-1F12-4519-AA28-3433684C2B4D
Partition table holds up to 128 entries
First usable sector is 34, last usable sector is 977105026
Partitions will be aligned on 8-sector boundaries
Total free space is 216 sectors (108.0 KiB)
Number Start (sector) End (sector) Size Code Name
1 40 409639 200.0 MiB EF00 EFI System Partition
2 409640 197302423 93.9 GiB AF00 MACOS
3 197302424 198571959 619.9 MiB AB00 Recovery HD
4 198572032 977104888 371.2 GiB 0700 Microsoft basic data
Command (? for help): W
Final checks complete. About to write GPT data. THIS WILL OVERWRITE EXISTING
PARTITIONS!!
Do you want to proceed? (Y/N): Y
OK; writing new GUID partition table (GPT) to /dev/rdisk0.
Warning: Devices opened with shared lock will not have their
partition table automatically reloaded!
Unable to open device '/dev/rdisk0' for writing! Errno is 1! Aborting write!
Command (? for help):