(if you are running XP) Have you applied SP2?
What is the state of the "Zero Wireless Configuration" service at the time you insert your Cisco NIC?
What version of the NIC drivers are you using? As of a couple weeks ago, I believe the current version is Wizard 2.1.
Follow the downloads | wireless path and get the latest drivers ... there are / were, Ah ...Um, "issues" with some of the 1.X flavors....
Good Luck
Scott