Wireless Keyboard and mouse not detected

Yesterday, I plug my wireless Mouse and Keyboard in my Desktop to take effect I restart my desktop when booting up no errors in the screen but.
The keyboard and mouse are not functioning the Light of the mouse are ok. I cannot use my mouse and keyboard its because they not work properly Or functionally My OS XP PROFESSIONAL
RAM 512
HARD DISK 80gb
ECS MOTHERBOARD
AMD ATLON X2 2.4GHz
Please help me.
Thanks.
Blackjan
