[boost] Access is denied for the "bootstrap" command

Hi, In order to use the serialization files... I need to build them... I have to go to the BGL directory from the command prompt and enter the "bootstrap" command... It works on some machines... But on my machine it gives me: "Building Boost.Build engine Access is denied. Failed to build Boost.Build engine. Please consult bootstrap.log for further diagnostics" My machine is an HP Workstation and I'm using Windows 7 professional edition... Why do you think I'm getting Access is denied?