Wireless Keyboard Error At Start Up

I have purchased another computer (A New Vostro 220 Dell). At start up I get an error page saying Wireless Keyboard error. I tried restore and the keyboard worked. After shutting down the next day at start up I got the wireless error again. I went to the Microsoft page and downloaded new drivers again it worked fine. After shutting down and coming back the next day I get the Wireless keyboard error and have to plug in the wired keyboard to be able to work on the computer?  This computer is running Vista 32 bit Business. I need to be able to move my keyboard around in my work situation and am limited with the wired one. Any help will be greatly appreciated.

Thanks in advance,
Kate