A company has decided to increase wireless infrastructure security by moving from WEP encryption to WPA2. Technicians change each WAP to the new encryption standard and users are given the new passwords. Many users are able to reconnect using the new authentication, but several users report an inability to reconnect. Which of the following is the MOST likely cause of the problem?

A.
The users who cannot connect are using older NICs without WPA2 support.

B.
The users who cannot connect are in areas without wireless coverage.

C.
The users who cannot connect have not been placed in the correct VLAN.

D.
The users who cannot connect have not specified the correct signal strength.