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function EnumModems: TStrings;
var
  R: TRegistry;
  s: ShortString;
  N: TStringList;
  i, j: integer;
begin
  Result := TStringList.Create;
  R := TRegistry.Create;
  try
    with R do
    begin
      RootKey := HKEY_LOCAL_MACHINE;
      if OpenKey('\System\CurrentControlSet\Services\Class\Modem', False) then
        if HasSubKeys then
        begin
          N := TStringList.Create;
          try
            GetKeyNames(N);
            for i := 0 to N.Count - 1 do
            begin
              CloseKey;
              OpenKey(N[i], False);
              s := ReadString('AttachedTo');
              for j := 1 to 4 do
                if Pos(Chr(j + Ord('0')), s) > 0 then
                  Break;
              Result.AddObject(ReadString('DriverDesc'), TObject(j));
              CloseKey;
            end;
          finally
            N.Free;
          end;
        end;
    end;
  finally
    R.Free;
  end;
end;