[NumLock]

Код:

function GetSpecialFolderLocation(Folder: Integer): String;
var
  ppidl: PItemIDList;
begin
  Result:='';
  ppidl:=nil;
  try
    if SHGetSpecialFolderLocation(0, Folder, ppidl)=S_OK then
    begin
      SetLength(Result, MAX_PATH);
      if SHGetPathFromIDList(ppidl, PChar(Result)) then
        Result:=IncludeTrailingPathDelimiter(PChar(Result))
      else
        Result:='';
    end;
  finally
    if ppidl<>nil then CoTaskMemFree(ppidl);
  end;
end;

Код:

GetSpecialFolderLocation(CSIDL_APPDATA);