Ty:
Look at Work Environment > Tool Schemes > Tool Settings Dialog Boxes > Window Tool >
Dimensions Marker to see if it is hidden. When making a change to your Work Environment, be sure to select the Scheme and click the
Redefine button to save the change.
You should add a Signature to your Profile (click the Profile button near the top of this page) with your ArchiCAD version and operating system (see mine for an example) for more accurate help in this forum.
David