ZBrush Not Sculpting
Strokes do nothing on the model
Also known as: ZBrush cannot sculpt · ZBrush brush not working · ZBrush edit mode · ZBrush T key · ZBrush model not editable · ZBrush brush does nothing
Quick answer
If strokes do nothing in ZBrush, you are probably not in Edit Mode or the tool is still a primitive. Select a tool, drag it on the canvas to draw it, then press T or click Edit to enter Edit Mode, and sculpt on it. Primitives such as a sphere need Make PolyMesh3D before they can be sculpted. Also check that Draw mode is on, and that Zadd is selected instead of Zsub.
How to fix it
If you drew a model, clicked elsewhere and it disappeared, it was dropped on the canvas and became a flat 2.5D pixol, so press Ctrl+N to clear and draw again. Check that the right SubTool is selected in the SubTool palette, and that a mask is not covering the area you want to sculpt. A very small Draw Size or Intensity also makes a stroke look like nothing, so try increasing them.
