Cannot export Private keys

Hi there.

We have just built a Windows 2008R2 Enterprise PKI.

The PKI is up and running fine, however when I am trying to sign a certificate with the Root CA with the "Export Private Key" option enabled, once the certificate has been issued, the keys are not exportable.

Below is the certificate inf file that was used to create the request. Note that "Exportable=TRUE"

[Version]
Signature="$Windows NT$"

[NewRequest]
Subject="CN=STG414262.clientdev.intradev.stg.com.au"
KeySpec=1
KeyLength=2048
Exportable=TRUE
MachineKeySet=TRUE
PrivateKeyArchive=FALSE
UserProtected=FALSE
UseExistingKeySet=FALSE
ProviderType=1
RequestType=PKCS10
ProviderName="Microsoft Strong Cryptographic Provider"
KeyUsage=0xF0
Silent=FALSE
SMIME=TRUE

[EnhancedKeyUsageExtension]
OID="1.3.6.1.5.5.7.3.1"
OID="1.3.6.1.5.5.7.3.2"

[RequestAttributes]
CertificateTemplate="Machine"
SAN="dns=stg414262.clientdev.intradev.stg.com.au"

Thanks.

Gerald Sullivan.