Whether or not edding permanent spray will stick to "old" paint depends on the formula of the old paint. Unfortunately, we cannot make any statement about this without more precise details. There are different formulations for paints: acrylic paints, nitro-combi paints, synthetic resin paints, water-based paints. All the above mentioned varnishes can be overpainted with synthetic resin varnishes. Synthetic resin varnishes can only be overpainted with synthetic resin varnishes. Acrylic paints such as edding permanent sprays cannot be painted over synthetic resin. This would cause the paint to "pull up" due to the incompatibility. It is therefore important to know what the base of the paint to be painted over is.