I would first look for an update to see if the firmware is up to date.
Second, try turning off the encryption and see if you can connect.
If you can, then add the encryption and passwords to all the computers again.
Hope this helps.
***If you told us what type of router, which version of windows and what program, if any you are using to connect, you answer may get more detailed.
My Internet Explorer 6 connects with unsecure wireless networks but it doesn?t connect with my secure one. My computer shows the connection to my network but IE doesn?t recognize it (although I can browse the web via unsecure networks in the surrounding area). I've tried everything I can think of, including checking the other two computers we have networked, but am not making progress. Any suggestions are appreciated.