What is this?

[Celestial]

There are certain threads that I click and then it says: an administrator has required you to enter a password to access this forum.

WTF does this mean and why is it happening.

 

[Jack's Smirking Revenge]

It means that the forum the thread is located in is password protected, and requires you enter the correct password to be able to view the forum.
They're all threads from the Survivor though, so you aren't going to get the password.

EDIT: Actually, turns out we can view them. BustaMo made a thread with the passwords.

 

[Celestial]

OK, I thought someone on my comp did something to lock out stuff in this forum.

 

[BustaMo]

Yeah you should have access to every forum you are able to view as a member. The one difference like stated above are the Huts for the Survivor participants. The passwords are located here: http://www.finalfantasyforums.net/news-and-updates/survivor-hut-passwords-11592.html