public string PortalProjectCustomDefaultToolbox {get; set;}

// access the current options
var def_home = ApplicationOptions.GeneralOptions.PortalProjectCustomHomeFolder;
var def_gdb = ApplicationOptions.GeneralOptions.PortalProjectCustomDefaultGeodatabase;
var def_tbx = ApplicationOptions.GeneralOptions.PortalProjectCustomDefaultToolbox;
var deleteOnClose = ApplicationOptions.GeneralOptions.PortalProjectDeleteLocalCopyOnClose;
var def_location = ApplicationOptions.GeneralOptions.PortalProjectDownloadLocation;


// set the options
ApplicationOptions.GeneralOptions.PortalProjectCustomHomeFolder = @"E:\data";
ApplicationOptions.GeneralOptions.PortalProjectCustomDefaultGeodatabase = @"E:\data\usa.gdb";
ApplicationOptions.GeneralOptions.PortalProjectCustomDefaultToolbox = @"E:\data\usa.tbx";
ApplicationOptions.GeneralOptions.PortalProjectDeleteLocalCopyOnClose = false;
ApplicationOptions.GeneralOptions.PortalProjectDownloadLocation = @"E:\data";