Bootcamp the startup disk cannot be partiitoned I cannot install Bootcamp because it gives me an error message of "The startup disk cannot be partitioned".
This is the result of diskutil list

/dev/disk0 (internal):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                         121.3 GB   disk0
   1:                        EFI EFI                     314.6 MB   disk0s1
   2:                 Apple_APFS Container disk2         121.0 GB   disk0s2

/dev/disk1 (internal, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *3.0 TB     disk1
   1:                        EFI EFI                     209.7 MB   disk1s1
   2:                 Apple_APFS Container disk2         1.9 TB     disk1s2
   3:       Microsoft Basic Data OSXRESERVED             8.0 GB     disk1s3
   4:       Microsoft Basic Data BOOTCAMP                1.1 TB     disk1s4

/dev/disk2 (synthesized):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      APFS Container Scheme -                      +2.0 TB     disk2
                                 Physical Stores disk0s2, disk1s2
   1:                APFS Volume Macintosh HD            913.9 GB   disk2s1
   2:                APFS Volume Preboot                 42.2 MB    disk2s2
   3:                APFS Volume Recovery                517.0 MB   disk2s3
   4:                APFS Volume VM                      24.6 KB    disk2s4

/dev/disk3 (disk image):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                            CCCOMA_X64FRE_EN-US... +4.7 GB     disk3

/dev/disk4 (disk image):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                            Boot Camp              +1.2 GB     disk4


and diskutil cs list

No CoreStorage logical volume groups found
This is a very common question. Again, here is the commands you need to enter in a Terminal application window.

The next two commands will remove the disk1s4 partition labeled BOOTCAMP and the disk1s3 partition labeled OSXRESERVED 

sudo diskutil eraseVolume free none disk1s4
sudo diskutil eraseVolume free none disk1s3


The next command return the free space back to the disk1s2 APFS container partition.

sudo diskutil apfs resizeContainer disk1s2 0