format PE64 GUI 5.0
entry start

include 'win64a.inc'

section '.data' data readable writeable

  _title db 'Win64 program template',0
  _class db 'FASMWIN64',0

  wc WNDCLASSEX sizeof.WNDCLASSEX,0,WindowProc,0,0,NULL,NULL,NULL,COLOR_BTNFACE+1,NULL,_class,NULL

  msg MSG

section '.code' code readable executable

  start:
        sub     rsp,8           ; Make stack dqword aligned

        invoke  GetModuleHandle,0
        mov     [wc.hInstance],rax
        invoke  LoadIcon,0,IDI_APPLICATION
        mov     [wc.hIcon],rax
        mov     [wc.hIconSm],rax
        invoke  LoadCursor,0,IDC_ARROW
        mov     [wc.hCursor],rax
        invoke  RegisterClassEx,wc

        invoke  CreateWindowEx,0,_class,_title,WS_VISIBLE+WS_DLGFRAME+WS_SYSMENU,128,128,256,192,NULL,NULL,[wc.hInstance],NULL

  msg_loop:
        invoke  GetMessage,msg,NULL,0,0
        or      eax,eax
        jz      end_loop
        invoke  TranslateMessage,msg
        invoke  DispatchMessage,msg
        jmp     msg_loop

  end_loop:
        invoke  ExitProcess,[msg.wParam]

proc WindowProc uses rbx rsi rdi, hwnd,wmsg,wparam,lparam

; Note that first four parameters are passed in registers,
; while names given in the declaration of procedure refer to the stack
; space reserved for them - you may store them there to be later accessible
; if the contents of registers gets destroyed. This may look like:
;       mov     [hwnd],rcx
;       mov     [wmsg],edx
;       mov     [wparam],r8
;       mov     [lparam],r9

        cmp     edx,WM_DESTROY
        je      wmdestroy
  defwndproc:
        invoke  DefWindowProc,rcx,rdx,r8,r9
        jmp     finish
  wmdestroy:
        invoke  PostQuitMessage,0
        xor     eax,eax
  finish:
        ret

endp

section '.idata' import data readable writeable

  library kernel32,'KERNEL32.DLL',\
          user32,'USER32.DLL'

  include 'apia\kernel32.inc'
  include 'apia\user32.inc'    

; Component Object Model usage demonstration

format PE64 GUI 5.0
entry start

include 'win64a.inc'

struc GUID def
 {
   match d1-d2-d3-d4-d5, def
    \{
      .Data1 dd 0x\#d1
      .Data2 dw 0x\#d2
      .Data3 dw 0x\#d3
      .Data4 db 0x\#d4 shr 8,0x\#d4 and 0FFh
      .Data5 db 0x\#d5 shr 40,0x\#d5 shr 32 and 0FFh,0x\#d5 shr 24 and 0FFh,0x\#d5 shr 16 and 0FFh,0x\#d5 shr 8 and 0FFh,0x\#d5 and 0FFh
    \}
 }

interface ITaskBarList,\
           QueryInterface,\
           AddRef,\
           Release,\
           HrInit,\
           AddTab,\
           DeleteTab,\
           ActivateTab,\
           SetActiveAlt

CLSCTX_INPROC_SERVER        = 0x1
CLSCTX_INPROC_HANDLER       = 0x2
CLSCTX_LOCAL_SERVER         = 0x4
CLSCTX_INPROC_SERVER16      = 0x8
CLSCTX_REMOTE_SERVER        = 0x10
CLSCTX_INPROC_HANDLER16     = 0x20
CLSCTX_INPROC_SERVERX86     = 0x40
CLSCTX_INPROC_HANDLERX86    = 0x80
CLSCTX_ESERVER_HANDLER      = 0x100
CLSCTX_NO_CODE_DOWNLOAD     = 0x400
CLSCTX_NO_CUSTOM_MARSHAL    = 0x1000
CLSCTX_ENABLE_CODE_DOWNLOAD = 0x2000
CLSCTX_NO_FAILURE_LOG       = 0x4000
CLSCTX_DISABLE_AAA          = 0x8000
CLSCTX_ENABLE_AAA           = 0x10000
CLSCTX_FROM_DEFAULT_CONTEXT = 0x20000

ID_EXIT = IDCANCEL
ID_SHOW = 100
ID_HIDE = 101

IDD_COMDEMO = 1

section '.data' data readable writeable

 CLSID_TaskbarList GUID 56FDF344-FD6D-11D0-958A-006097C9A090
 IID_ITaskbarList GUID 56FDF342-FD6D-11D0-958A-006097C9A090

 ShellTaskBar ITaskBarList

section '.code' code readable executable

 start:
        sub     rsp,8           ; Make stack dqword aligned

        invoke  CoInitialize,NULL
        invoke  CoCreateInstance,CLSID_TaskbarList,NULL,CLSCTX_INPROC_SERVER,IID_ITaskbarList,ShellTaskBar

        invoke  GetModuleHandle,0
        invoke  DialogBoxParam,rax,IDD_COMDEMO,HWND_DESKTOP,COMDemo,0

        cominvk ShellTaskBar,Release

        invoke  ExitProcess,0

proc COMDemo uses rbx rsi rdi, hwnd,msg,wparam,lparam
        mov     [hwnd],rcx
        cmp     edx,WM_INITDIALOG
        je      wminitdialog
        cmp     edx,WM_COMMAND
        je      wmcommand
        cmp     edx,WM_CLOSE
        je      wmclose
        xor     eax,eax
        jmp     finish
  wminitdialog:
        jmp     processed
  wmcommand:
        cmp     r8,BN_CLICKED shl 16 + ID_EXIT
        je      wmclose
        cmp     r8,BN_CLICKED shl 16 + ID_SHOW
        je      show
        cmp     r8,BN_CLICKED shl 16 + ID_HIDE
        jne     processed
  hide:
        cominvk ShellTaskBar,HrInit
        cominvk ShellTaskBar,DeleteTab,[hwnd]
        jmp     processed
  show:
        mov     rbx,[ShellTaskBar]
        comcall rbx,ITaskBarList,HrInit
        comcall rbx,ITaskBarList,AddTab,[hwnd]
        comcall rbx,ITaskBarList,ActivateTab,[hwnd]
        jmp     processed
  wmclose:
        invoke  EndDialog,[hwnd],0
  processed:
        mov     eax,1
  finish:
        ret
endp

section '.idata' import data readable

  library kernel,'KERNEL32.DLL',\
          user,'USER32.DLL',\
          ole,'OLE32.DLL'

  import kernel,\
         GetModuleHandle,'GetModuleHandleA',\
         ExitProcess,'ExitProcess'

  import user,\
         DialogBoxParam,'DialogBoxParamA',\
         EndDialog,'EndDialog'

  import ole,\
         CoInitialize,'CoInitialize',\
         CoCreateInstance,'CoCreateInstance'

section '.rsrc' resource data readable

  directory RT_DIALOG,dialogs

  resource dialogs,\
           IDD_COMDEMO,LANG_ENGLISH+SUBLANG_DEFAULT,comdemo

  dialog comdemo,'Taskbar item control',70,70,170,24,WS_CAPTION+WS_POPUP+WS_SYSMENU+DS_MODALFRAME
    dialogitem 'BUTTON','Show',ID_SHOW,4,4,45,15,WS_VISIBLE+WS_TABSTOP
    dialogitem 'BUTTON','Hide',ID_HIDE,54,4,45,15,WS_VISIBLE+WS_TABSTOP
    dialogitem 'BUTTON','Exit',ID_EXIT,120,4,45,15,WS_VISIBLE+WS_TABSTOP
  enddialog    

yes, thanks you both, guys. now just to have more examples. I do have 64bit machine, but only 32bit XP OS, so i can't help:|

Version: Windows XP Professional x64 Edition, 180-day Evaluation (English)