Cannot remove dvd drive from drive bay

my system spec are:ystemax Ascent HA3700 RTS PC

Serial number: 106127505
Order number: E37286880101
Ship Date: 1-13-2006
Your Warranty Expires on: 1/13/2007

Your computer contains the following:

(1) FREE Consumer Software
(1) Systemax Support Kit
(1) Mini-Tower mATX Chassis w/350W PS K8M800 Motherboard
(1) Microsoft Windows XP Home Edition w/ Service Pack 2
(1) AMD Athlon 64 3700+ Soc 754 CPU Complete
(1) 1GB DDR400 PC3200 Memory (512MB x 2)
(1) 250GB 7200RPM 3G SATA II Hard Drive
(1) ATI Radeon 9550 256MB AGP (1DVI / 1VGA)
(1) 16x (max) DVD ROM Drive
(1) 16x DVD-/+R/RW Dual Layer Drive
(1) Cyber Acoustics 2016 2-Piece Speakers
(1) 56K V.92 PCI Data/Fax Modem
(1) Logitech Deluxe Keyboard Black PS/2
(1) 9-in-1 USB Card Reader
(1) Logitech Black Optical Mouse
the problem is i cannot remo the dvd from the drive bay to install a new one. on the side of the drive bay it looks like a lock. is it possible that i need a key to unlock the drive bay?

problem solved. there were clips on the front ofthe case.