Page Password still not working

I am trying to password protect a page.

Once I publish the page and visit it on another machine I am UNABLE to successfully view the contents of the password protected page.

In another topic, someone propose the solution above, but it seems to work only for some versions. I had version 2.3.1 and don′t work for me at all.

Solution given in another topic related:
change the line in wp-pass.php
from:
wp_safe_redirect(wp_get_referer());
to:
wp_safe_redirect(wp_get_referer() . ‘?’);

IT WOULD BE GREAT IF SOMEONE CAN HELP US… It seemes that many of us have the same problem. Thanks a lot if you can help us!