Now I think I understand what you meant.
It happens to me very often and I saw it in forum replies too. Given links to help.sap.com pages do not work for one user, while another can click the same link and it opens without any problem.
I even copied the link into a new browser window and it opened, while clicking the link itself just brought the standard 404 error.
You could try to open the link in private mode of the browser.
