no wireless network found after removing group policy

Hi all

I have a Win2003 R2 Std Svr with AD domain.
I have a few notebooks using wireless connection.
These few notebooks are all domain computers.

I created a wireless security policy, and then removed it.
Before the wireless security policy, the few notebooks worked fine with
wireless connection.

After the wireless security was created and then removed, the few notebooks
now can't find any wireless network available in range eventhough there is a
wireless access point next to them.

I am sure that access point is configured properly because workgroup
notebooks that have not joined the AD domain are able to connect to it
without problem.

Please help !

Regards,
Ju