Thanks guys. Fortunately, I was able to remember the old password for the "Login" keyring. So I was able to change it from within Seahorse (the "Passwords and Keys" application program in Gnome). So that problem is solved. But . . . while in Seahorse, I realized that in the "Certificates" section on the left side of the window, there was another folder with a lock icon, labeled "Gnome 2 Key Storage". There seem to be no entries showing within it. The "Gnome 2 Key Storage" folder can only be locked or unolcked with the OLD password, not the NEW password. And it can not be changed or deleted from within Seahorse. I am using Gnome 3, so I don't know why it is there, but I don't know if it can be removed, and even if so, then how? And I do wish that I could at least change the password for it, since I hate to keep track of an old password just in case I need to use it to unlock the folder sometime.