Logging in works, get kicked out right after

[Silverburn]

I can log into my account, but everytime I click one of those pages(like Training, or Armory) I get this: You are not logged in. Please try to login again. Please note that cookies MUST be enabled to login, for security reasons. Only your player ID (not password or email) are kept in the cookie.

So here's what I did

1) clear cache and all other data, no effect

2) checked cookies, they are enabled

3) checked firewall, no problem

4) used Internet Explorer: didn't have this problem.

I'm using Firefox 3.0

The onlything I can think of is that an add-on must have altered some configuration.

If so, I wish I knew which one

Screenshot
EDIT: I just noticed that this also happens on Quantumgate, but NOT on ascended, I can play ascended with FF3 just fine

[Silverburn]

Right, I've restarted firefox in safe mode, thusly resetting all my values and configurations back to default settings.

Now I no longer have this problem.

[DaDigi]

Okay then.