Suddenly the Clip Volume cannot be modified or edited. The green and blue arrow handles used to modify the clip volume are not shown or available. The white rectangular section clip box is displayed but clicking on this has not effect. The same Clip Volume can be modified when opened on other machines.
Image 1 - no Clip Volume Edit Handles
Image 2 - Disable Handles, Element Selection Tool
Image 3 - Clip Volume Edit Handles displayed
Note: If there is no white rectangle section clip box displayed either (Iamge 4), and the Disable Handles option is switched off left click on the Marker icon in the view to show the Edit Clip Volume Handles as shown in Image 5 below
Image 4 - No white rectangle section clip box shown
Image 5 - Clicking on Marker shows Clip Volume Edit Handles