...does not necessarily mean that you have a problem. It just means that you have an IP configuration, just not valid for your network. You may have no IP configuration at all, such as when WLAN Config has failed and you have 0.0.0.0 as an IP address or you may have an APIPA address (auto configured). In any case, as NexS has suggested, more and concise details regarding the hostory of your 'issue' would go a long way towards getting it resolved.
Windows Update will most likey not be the cause of your woes, however. The culprit will probably be the fact that your computer rebooted after the update and hosed the WLAN connection (common Windows issue), and all this means is that you may have to enter the WLAN details manually.
As in, create the connection afresh. Delete the WLAN network and "Set up a new connection" then "Manually connect to a woreless network" and see how this grabs ya...