[bedoig]

Considering the amount of other duplicate threads, I wouldn't be too hard on the OP because of that. Looks more like an issue with the migration from one server to the other.

As for your question, it is hard to make a real diagnosis over the web, but here are a few things to try:

Remove all network security. If you can get access with it running wide open, you know it is some kind of security conflict.

Turn WiFi to "Best Performance." Start-->Settings-->Connections-->Wireless LAN-->Power Mode.

Are you running WMWiFiRouter?
Make sure you are accepting an assigned IP and not determining your own. Also, make sure you are searching for access points, and not just computer to computer connections.