unable to disconnect from internet

using gateway laptop with intel pro/wireless 2200bg, using cable modem and linksys wrt54g router for wifi. everything works fine 'til i wish to disconnect, any attempt to disable wifi gives error message 'it is not possible to disable the connection at this time. the connection may be using one or more protocols that do not support plug and play, or it may have been initiated by another user or the system account.' have done numerous av and malware searches and come up with nothing. have even updated drivers. nothing helps