Wooden doors often double as poster boards, display areas for the week's shopping schedule or list "cautions" to be observed when entering a bedroom. When you hang the first poster, the hole left by the pin is barely noticeable, but as you add more and change the ones that are already there, the holes eventually become impossible to ignore. The best time to repair them is when you're planning to paint the door, but you can do it anytime. The job is a little more challenging when the door has a stain and a clear finish.
Wash the door surface with a solution of grease-cutting detergent and warm water. Dry it, using a clean rag.
Fill the pinholes with drywall joint compound if you plan to repaint the door or the door is already painted white or off-white.
Trowel the joint compound over the holes with a 4-inch drywall blade and scrape off the excess. Give it about an hour to dry. If you're going to repaint, sand the door lightly with 150-grit sandpaper to remove all the residue. Alternatively, if you're not going to repaint, wipe the door with a damp rag. The rag will moisten and remove any joint compound still on the door.
Fill the pinholes with wood filler if the door is stained and painted. Choose a latex filler that is the same color as the stained and finished wood.
Trowel the filler into individual holes with a putty knife and scrape off the excess. Wipe the area around the repair immediately to remove excess filler before it dries, using a damp rag.
Let the filler dry. If you want to hide the pinholes even more, wipe stain over the repair with a rag and wipe off the excess immediately. Apply one coat of clear finish, using a paintbrush or spray can.