NAS-R3, latest available firmware. After opening the web GUI, I enter the password and... return to the login form again. When I enter wrong password, I get a warning po-up. If I enter the correct password, I return to the login screen again. Tried IE8, Firefox 3.5.3 and Firefox 2.0 - same result.

Yesterday I could log in without any problem. Since then, nothing was done to the system.

I would not like to restart the whole system since it is a production one. Is there a way to somehow restart the web GUI?

Thanks.