Hey - Key in 123456 and observe. Otherwise, it will largely depend on the model and make of your device though all Android powered devices generally involve reinstalling the main device's firmware to clear a forgotten or unknown Privacy Protection Password. Something you can either do yourself (provided you have a copy of the software/ROM pack specific to your device model) or you can go via your retailer (the shop you purchased the device from). Do comment below with your device's brand and model name/number and we will gladly advise further.