"Data not found" error when querying Provider vDC for Storage Profile

I am trying to create a vDC with a Storage profile defined. I am getting a "Data not found" when I run the following command:

ReferenceType providerVdcStorageProfileRef = pvdc.GetProviderVdcStorageProfileRefs().FirstOrDefault();

I can query networks from the pvDCwithout a problem.

Here is more of the code:

                ReferenceType pvdcRef = admin.GetProviderVdcRefByName("My Provider vDC");
                createVdcParams.ProviderVdcReference = pvdcRef;
                ProviderVdc pvdc = ProviderVdc.GetProviderVdcByReference(objConn.client, pvdcRef);

                ReferenceType providerVdcStorageProfileRef = pvdc.GetProviderVdcStorageProfileRefs().FirstOrDefault();

                vdcStorageProfile.ProviderVdcStorageProfile = providerVdcStorageProfileRef;
                createVdcParams.VdcStorageProfile = new VdcStorageProfileParamsType[] { vdcStorageProfile };

Can anyone help me out?