|You may have forgotten to "save" the wireless key (password) the first time you set up that connection. The first time you set it up and when it connects, a box pops up with two boxes to tick to save the connection. Windows then remembers the wireless key.|
Delete that Network connection in Windows Networking & Sharing Center.
Bring up the list of available networks and click on your router's SSID.
Enter the wireless key (what you incorrectly call the password).
When it connects successfully you should get a prompt to "Save".