Disable LogOff, TaskManager and ShutDown on Win NT systems (2000/XP)

If you want to hide your program from Windows NT compatibile systems (2000/XP) you'll need to mess with the registry...

The Enable CTRLALTDEL procedure accepts a boolean value for the YesNo parameter. If you send False, after the code has executed, if the user presses ctrl-alt-del, on the Windows Security dialog box, buttons [Task Manager], [Shut Down] and [Log off] will be disabled.

Usage:
EnableCTRLALTDEL(False)

procedure EnableCTRLALTDEL(YesNo : boolean) ;
const
sRegPolicies = '\Software\Microsoft\Windows\CurrentVersion\Policies';
begin
with TRegistry.Create do
try
RootKey:=HKEY_CURRENT_USER;
if OpenKey(sRegPolicies+'\System\',True) then
begin
case YesNo of
False:
begin
WriteInteger('DisableTaskMgr',1) ;
end;
True:
begin
WriteInteger('DisableTaskMgr',0) ;
end;
end;
end;
CloseKey;
if OpenKey(sRegPolicies+\Explorer\',True) then
begin
case YesNo of
False:
begin
WriteInteger('NoChangeStartMenu',1) ;
WriteInteger('NoClose',1) ;
WriteInteger('NoLogOff',1) ;
end;
True:
begin
WriteInteger('NoChangeStartMenu',0) ;
WriteInteger('NoClose',0) ;
WriteInteger('NoLogOff',0) ;
end;
end;
end;
CloseKey;
finally
Free;
end;
end;