NX1926 series has 5 operation subtypes that fail to open the bitmap file. Missing bitmaps:
cam_mill_floor_facing_tip.bmp
cam_mill_pocketing_tip.bmp
cam_mill_de_profile_wall_only_tip.bmp
cam_mill_2d_profile_tip.bmp
cam_mill_chamfer.bmp
The problem is resolved in the NX1953 series.
Solution
As a workaround...until you can upgrade to the NX1953 version...
Convert the following images to bitmaps and place them in the $UGII_CAM_TEMPLATE_IMAGE_DIR folder.
Note: $UGII_CAM_TEMPLATE_IMAGE_DIR is the OOTB location for the bitmaps. Your site may have the images in a unique location. Contact PLMS, formerly GTAC, if that is your situation.