Joomla 1.5.4 Problem

[3dmagicaldesign]

Hi Guys


I have the following problem:

I installed this joomla on my server, it was working perfect until now. I didn't modify nothing on it, it was just inactive for some minutes, then, when I tried to work on it, I was asked to login again, then I tried to login but I received an error and it didn't allow me to login:

This is what I received:
"Use a valid username and password to gain access to the Administrator Back-end.W[/I

I tried using a wrong user and password and it showed me the following error:
Username and password do not match

it looks like joomla is stucked, when I fill the boxes with the correct information it doesn't take to to my admin panel, just stays on the login page, but once I fill the boxes with the wrong user and password it shows a login error .

Please help, I really don't know why it could be happening.

 

[jnjc]

Maybe it's a cookie issue, have you tried clearing your cookies and trying again ? Maybe try login from a different browser...

Addition...

I am pretty new to joomla but I have seen instances where it opens a new window when you submit a form (usually after I've been logged in and doing lots of different things). If this is the case and the window gets minimised then it'll look like it's doing nothing but in reality it's sending you page to the minimised window...