Open a Block From the DesignCenter Window in the Block Editor
Click View tab Palettes panelDesignCenter. Find
Right-click a block in the DesignCenter content area and select Block Editor.
Update a Block Definition With DesignCenter
Click View tab Palettes panel DesignCenter. Find
Right-click a block in the DesignCenter content area and select Redefine Only or Insert and Redefine.
Note: If the source of the block that you want to update is an entire drawing file rather than a block definition within a drawing file, right-click the drawing's icon in the DesignCenter content area. Click Insert as Block.