Could you post again with more information - "it doesn't work" isn't much to go on. For example, does it not see routers at all, is unable to connect, connects but cannot authenticate or get an IP address? Does it have problems with all routers, one specific router, those using encryption? The more information we have, the more change we have of identifying the problem.
Also, what changed with the update? Was it an android version change (e.g. 4.3 to 4.4) or just a minor/operator update?