Discombobulated by Toolbar image

I am using VS2008. I have a CMFCToolBar toolbar that seems to be missing a button. Here is the image of the toolbar:



The button that is missing is (delta Z) which should come right after delta y.

Here is the resource file

IDR_STRUCTURAL_TOOLBAR TOOLBAR  24, 23
BEGIN
    BUTTON      ID_DISPLACEMENT_X
    BUTTON      ID_DISPLACEMENT_Y
    BUTTON      ID_DISPLACEMENT_Z
    BUTTON      ID_DISPLACEMENT_SUM
    BUTTON      ID_DISPLACEMENT_RX
    BUTTON      ID_DISPLACEMENT_RY
    BUTTON      ID_DISPLACEMENT_RZ
    SEPARATOR
    BUTTON      ID_THERMAL_TEMP
    BUTTON      ID_STRUCTURAL_TEMP
    SEPARATOR
    BUTTON      ID_STRESS_X
    BUTTON      ID_STRESS_Y
    BUTTON      ID_STRESS_Z
    BUTTON      ID_STRESS_XY
    BUTTON      ID_STRESS_YZ
    BUTTON      ID_STRESS_XZ
    SEPARATOR
    BUTTON      ID_STRESS_1
    BUTTON      ID_STRESS_2
    BUTTON      ID_STRESS_3
    SEPARATOR
    BUTTON      ID_STRESS_INT
    BUTTON      ID_STRESS_EQV
    SEPARATOR
    BUTTON      ID_NODE_PLOT
    BUTTON      ID_ELEMENT_PLOT
END

Here is the bmp image used to create the toolbar.

So the question is, where is Delta Z ???

I just don't understand how this is happening. Thanks in advance for any help.