Something strange happened at home.
First my laptop would connect to the Internet / router but would not pickup an IP number and thus not browse, ping etc.
Playbook was still ok, but then that would not reconnect when I disconnected (to check things)
WIN7 PC
After a lot of playing with settings, I changed my Wireless Security settings
From 'WPA2-Personal' to 'WPA-Personal' (Encryption type TKIP)
Reconnected and now everything's ok
PLAYBOOK
It says it's using WPA Personal, the password is ok,
Dual Band, Auto obtain IP, Allow inter-access (all selected)
Still no joy
Obviously nothing has been changed on my home network/router.
You maybe should have unplugged your router for a minutes and plugged it back in. Then reboot both devices. Which is it? You changed the security on the router or you changed nothing?
Have you deleted the profile from the pb and then try to add it again?
I would try unplugging router and modem and turn off computers and playbook. Wait 2 minutes.
Then plug modem back in and let it boot up so all the lights that are supposed to be on are.
Then plug router in and let it boot up so all lights are on.
Now turn on computers and playbook and see if they can connect.