Receiving an S_OK but an HRESULT_FROM_WIN32(ERROR_INVALID_HANDLE) from get_CurrentMediaStatus() but not from get_CurrentPhysicalMediaType()

//  This call returns an error...
unsigned int getMediaStatus( char cDriveLetter )
{
    HRESULT  hResult;
    IMAPI_FORMAT2_DATA_MEDIA_STATE  mediaStatus = IMAPI_FORMAT2_DATA_MEDIA_STATE_UNKNOWN;
    int  iPos;
 
 
    //  Select the drive to get the status of
    for( iPos = 0; iPos < driveLetters.size(); iPos++ )
    {
        if ( driveLetters[ iPos ] == cDriveLetter )
        {
            hResult = discFormat2Data[ iPos ]->get_CurrentMediaStatus( &mediaStatus );
            break;
        }
    }
    
    return( mediaStatus );
}
 
 
//  This call does not return an error, but the correct value
unsigned int getMediaType( char cDriveLetter )
{
    HRESULT  hResult;
    IMAPI_MEDIA_PHYSICAL_TYPE  mediaType = IMAPI_MEDIA_TYPE_UNKNOWN;
    int  iPos;
 
 
    //  Select the drive to get the status of
    for( iPos = 0; iPos < driveLetters.size(); iPos++ )
    {
        if ( driveLetters[ iPos ] == cDriveLetter )
        {
            hResult = discFormat2Data[ iPos ]->get_CurrentPhysicalMediaType( &mediaType );
            break;
        }
    }
    
    return( mediaType );
}