Where does the Apple Bootcamp software store the drive definitions on the windows partition? I removed my CDROM and added an SSD to my MACBOOK PRO I7 (mid 2010) in it's place. I can boot into my windows partition, however while I am in bootcamp(in WINDOWS) I can only select to start from old OSX partition and not my new SSD. I always have to hold OPTION key down to be able to boot form the SSD when coming out of windows. I've looked for INI files related to bootcamp in the \Program/ Files Directory and user directory. Where can I find the Drive definitions, so that I can add my new SSD? BTW, it boots just as fast as many newer models now.

diskutil  list
/dev/disk0 (internal, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *120.0 GB   disk0
   1:                        EFI EFI                     209.7 MB   disk0s1
   2:                 Apple_APFS Container disk2         119.8 GB   disk0s2

/dev/disk1 (internal, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *1.0 TB     disk1
   1:                        EFI EFI                     209.7 MB   disk1s1
   2:          Apple_CoreStorage MacHD                   898.3 GB   disk1s2
   3:                 Apple_Boot Recovery HD             650.0 MB   disk1s3
   4:       Microsoft Basic Data BOOTCAMP                101.0 GB   disk1s4

/dev/disk2 (synthesized):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      APFS Container Scheme -                      +119.8 GB   disk2
                                 Physical Store disk0s2
   1:                APFS Volume MacSSD                  36.6 GB    disk2s1
   2:                APFS Volume Preboot                 21.7 MB    disk2s2
   3:                APFS Volume Recovery                503.9 MB   disk2s3
   4:                APFS Volume VM                      5.4 GB     disk2s4

/dev/disk3 (internal, virtual):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                  Apple_HFS MacHD                  +898.0 GB   disk3
                                 Logical Volume on disk1s2
                                 76C259A6-63E8-45F6-9E3B-0D7F2AD246C9
                                 Unencrypted

/dev/disk4 (external, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:     FDisk_partition_scheme                        *1.0 TB     disk4
   1:               Windows_NTFS Backup                  1.0 TB     disk4s1
A drive is usually divided up into partitions. There is a table stored in the drive that contains this partition information. The Boot Camp software installed in Windows looks at this table to determine which partitions are bootable. APFS is fairly new and your Boot Camp software does not properly recognize bootable macOS volumes stored in APFS partitions. 

There is a workaround that can allow you to boot directly to your SSD from Windows. See the question: macOS partition disappered after installing windows 10 using bootcamp. I consider the accepted solution as a temporary fix. Apple may issue a Boot Camp update for Windows that will fix this problem. Or, Apple may  not.

Below are the steps to make this fix to your Mac. The commands need to be entered into a Terminal application window.


Create the new volume.  The diskutil command, shown below, shrinks the APFS container by 300 MB and creates the new 200 MB "Mac OS Extended (Journaled)" volume labeled "MacSSD via rEFInd". 

sudo diskutil ap resizeContainer disk1 119500M JHFS+ "MacSSD via rEFInd" 200M


After the command completes, restart the Mac.
Download the rEFInd Boot Manager software from this SourceForge web site. Enter the following commands to install the software to the "MacSSD via rEFInd" volume.

cd ~/Downloads/refind-bin-0.11.2
./refind-install --ownhfs /dev/disk0s3



  Note: The error message Could not set boot device property: 0xe00002bc was expected and can be ignored.

Configure the TextEdit application. Open TextEdit, then navigate to the "Preferences..." window. Uncheck all the "Options", as shown below. When finished, quit TextEdit.


Use the command below to navigate to the folder containing the refind.conf file. 

cd "/Volumes/MacSSD via rEFInd/System/Library/CoreServices"


Make a backup copy of this file.

cp refind.conf refind.conf.orignal


Open the file in the TextEdit application.

open -e refind.conf

Add the following lines to the end of the refind.conf file. You should be able to just cut and paste these lines. When finished, save the changes, then quit TextEdit.

#
# Added to make rEFInd silent. 
#
menuentry "MacSSD via rEFInd" {
    icon \System\Library\CoreServices\icons\os_mac.png
    volume "MacSSD"
    loader \System\Library\CoreServices\boot.efi
    ostype MacOS
    graphics on
}
timeout -1
hideui all
scanfor manual

Enter the following commands to modify the /etc/fstab file. This entry will instruct macOS not to mount the volume labeled "MacSSD via rEFInd" at startup.

sudo bash 
echo &gt;&gt;/etc/fstab
echo "LABEL=MacSSD\040via\040rEFInd none hfs rw,noauto" &gt;&gt;/etc/fstab    
exit



  Note: The character sequence \040 is just the octal representation of the space character.


When finished, restart the Mac.


Now when choosing Boot Camp from the Control Panel, you should get something similar to what is shown below.