Windows association failed

[firemonkey]

Not very good at explaining tech stuff so please bear with me.

Both desktop and laptop were connected via router. Desktop still connected but lost laptop connection and keep getting following error message ' windows association failed because windows didn't receive any response from the wireless router or access point'.
The thing is i was able to temporarily use an unsecured network before being booted off and wonder why i could do so whilst not being able to use my network.
Never had this problem before and router is new(3 weeks) and i guess ok because i have a connection via desktop.

Am using Vista basic