You cannot establish a WLAN connection, when you use WPA2 Enterprise in combination with AD login (Windows 2008 R2, Radius server). In the event log of the radius server, you see “Schannel error 47”, IDs 36887 and 36885.
The Trusted Root CA List is too long.
Have a look at this blog entry, it explains very well what you can do to solve this.
Create reg key HKEY_LOCAL_MACHINESYSTEMCurrentControlSetControlSecurityProvidersSCHANNELSendTrustedIssuerList as DWORD with value 0.