I am using Samsung CD ROM drive.For some days its tray
Is not functioning properly.It is not opening after pressing the eject key.After repeated pressing it occasionally opens.But after opening the tray when I press the same key it is ejecting spontaneously just after closing and I cannot close the tray... What is the cause and solution ?Please help me...

Check if the power cable to the drive is loose.

Right click on the drive icon in My Computer and select "eject" see if that works to open AND close the drive tray.

If it works, then the physical eject button is probably flaky. Not much you can do to fix it, unless your handy with a soldering iron and disasembly.

You can either get a new drive or if it works, continue using Window's eject feature.