Problem with my monitor

I've got a problem with my Samsung Syncmaster 913N where i cant get it to auto adjust and the OSD is locked. I've only had the monitor for just over a month and its been working fine, however i installed some new graphics drivers earlier and this meant the resolution changed on the desktop. When i press the auto adjust button a message pops up on the monitor saying "Auto Adjustment Locked". When i go into the monitors OSD i can change the brightness and contrast but all of the other pages are locked and it wont let me change anything. I cant find anywhere within the menu to unlock it and i cant seem to find anything helpful on Samsung's website.
Really do want to get this fixed as i now have 'smudge' lines all over the screen because its not all setup right :(