After a fresh XOOPS install, it still is broken.

Since a few hours ago, whenever I or any of my users has logged in, they can browse the forums or something for about 1-2 pages and then the page they have entered will have them not logged in. It doesn't log them out, like the Log Out link does, rather it's like they closed the browser window (they still show up under Who's Online for a little bit). They are just no longer logged in. I should also mention that this makes it impossible for me to access the admin area. Can anyone tell me a remedy for this situation, or offer a suggestion? Thank you in advance.

Thanks a million.

I created my site using XOOPS three days ago, and it's worked flawlessly up till now. This morning, when I went to the administration menu, I noticed that the "System" button is gone. The "Forums" and "News" buttons are still there, however, I can't get into anything in the system category.

However, I can still edit users if I go into their profile and click "edit profile" (isn't editing users in the System category?).

I don't know what I did to it to make this happen. Also: I am the only one with administrator access.

Can anyone help me? Thank you in advance.