Wifi on mac works but not windows xp

[lorcan64]

Had talk talk router upgrade yesterday and everything worked fine. Today wifi works on MacBook but not on PC Windows xp3. It appears in the list but won't connect on pc. Can connect to an unsecure weak connection on the list but it's not mine. Been in to router to chnage channel from auto to 11 as an eg

 

[Emerald]

delete the SSID profile in the network card properties of the PC and reconnect by reentering the password when asked

 

[lorcan64]

delete the SSID profile in the network card properties of the PC and reconnect by reentering the password when asked

Hi Emerald, thanks for that. I am not sure how to do that ie delete the ssid. Went into wireless network card properties and under the configure option of connect (using advanced option) ssid had a blank value. I actually put 0 and exited but nothing happened. when I went back in to configure I couldn't delete the zero

I am using xp home sp3 and my adapter is a buffalo wli-u2-kg54 which is quite old. Odd how it worked yesterday. It's nothing to do with the security is it or the WP2 etc ???

Many thanks