Problems logging into admin panel

I have serious problems getting logged into the admin panel. Everytime I entered the username and password, I get the logon window again. When I do succeed after many attempts and get into the admin panel, it acted strangely.
For instance, It will not remove or add when I want to set up my forums and categories, and when I execute an action, bang, straight back to the logon window, without saving the action. No chance of doing more than one command before being dispatched to the logon window in anyway. From thereon it is the same battle over again to no avail.

BTW, I emptied the cache a few times, restarted my computer. After 5 hours I am now desperate for help.
Any suggestions out there?

Hello and welcome to Editboard FOF.

Because you are new, here are useful links where you can look for answers :

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Moreover, if you don't find the answer for your question, don't hesitate to open a new topic since this section is made for this!

concerning your question, I informed our technicians of your problem, I will answer you as soon as they have found solution to your loging problem!

cordially