CORRECTION: There is a bug(?) in the previous version. Sorry... Many times, especially when dealing with Windows API functions, may need to manipulate numbers in the bit level This is an example on how to operate on bits and manipulate bits. It may be useful for the beginner I included some bit manipulation functions in BitUnit.pas unit I use Delphi 4, but you can compile it using Delphi 3 or 2. Just open the .dpr and ignore any errors when the form is loaded =================================================== Theodoros Bebekis Thessaloniki, Greece bebekis@mail.otenet.gr