Keyboard Problem!!!!

Yesterday I bought a new Keyboard for my PC but the problem i'am facing is that the left "shift" key is giving errors while typing. Holding the left "shift" key gives "|" and sometimes "\". for e.g, if i have to type "@" it gives "|@" or "\@". is there any fault in the keyboard or is it a driver issue??
OS: Windows 7 Ultimate(64 bit)
RAM: 4 Gb
CPU: i3 processor, Intel.
Please Help...