A certificate could not be found that can be used with this Extensible Authentication Protocol. 798

Install Certificate and Client Package and when I try to connect it shows the following error

"A certificate could not be found that can be used with this Extensible Authentication Protocol. (Error 798) For customised troubleshooting information for this connection"

I have checked both cert are installed under current user in both personal and trusted root, and have tried every resource we can

We have successfully installed using same settings & process on Windows 7 without problem, the log file is as follows
******************************************************************
Operating System      : Windows NT 6.2
Dialler Version        : 7.2.9200.16384
Connection Name       : Dxxxxxxxxx2
All Users/Single User : Single User
Start Date/Time       : 16/05/2013, 15:04:48
******************************************************************
Module Name, Time, Log ID, Log Item Name, Other Info
For Connection Type, 0=dial-up, 1=VPN, 2=VPN over dial-up
******************************************************************
[cmdial32] 15:04:48 22 Clear Log Event
[cmdial32] 15:04:51 04 Pre-Connect Event ConnectionType = 1
[cmdial32] 15:04:51 06 Pre-Tunnel Event UserName =  Domain =  DUNSetting = Dxxxxxxxxx2 Tunnel DeviceName =  TunnelAddress = azuregateway-xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx.cloudapp. net

Did you ever discover a solution for this? I'm testing now and running into the same issue with Windows 8. I generated my testing certificate with makecert per this:

A Windows Azure management certificate is an X.509 v3 certificate used to authenticate an agent, such as Visual Studio Tools for Windows Azure or a client application that uses the Service Management API, acting on behalf of the subscription owner to manage subscription resources. Windows Azure management certificates are uploaded to Windows Azure and stored at the subscription level. The management certificate store can hold up to 100 certificates per subscription. These certificates are used to authenticate your Windows Azure deployment.

Management certificates must have a key length of at least 2048 bits and should reside in the Personal certificate store. When the certificate is installed on the client, it should contain the private key of the certificate. To upload to the certificate to the Windows Azure Management Portal, you must export it as a .cer format file that does not contain the private key.
noteNote

    You can use the Certificates console to export and import certificates.

    To upload a management certificate to Windows Azure, go to the Settings page in the Management Portal, and then click MANAGEMENT CERTIFICATES.

To create your own self-signed management certificates, open a Visual Studio command prompt as an administrator, and then run the following command:
msdos

makecert -sky exchange -r -n "CN=<CertificateName>" -pe -a sha1 -len 2048 -ss My "<CertificateName>.cer"

The Makecert command stores the new certificate in the default Personal certificate store. For more complete information on generating a certificate, see Create a Service Certificate for Windows Azure.
WarningWarning
The private key associated with a certificate should be maintained in a secure location. After the .cer file is uploaded, anyone who has the private key can use the Service Management API to control the hosted service. This includes creating, deleting, and modifying services and storage accounts on your subscription that are associated with certificate.