Error: Country_id and Zone_id

Hi all I did was try to set up my mail, I went to my home page and got the following errors appear at the top of my page:
2012-02-11 10:42:31 - PHP Notice: Undefined index: country_id in /home/saltandp/public_html/Shop/system/library/tax.php on line 17

2012-02-11 10:42:31 - PHP Notice: Undefined index: zone_id in
/home/saltandp/public_html/Shop/system/library/tax.php on line 17

2012-02-11 10:42:31 - PHP Notice: Undefined index: country_id in /home/saltandp/public_html/Shop/system/library/tax.php on line 31

2012-02-11 10:42:31 - PHP Notice: Undefined index: zone_id in /home/saltandp/public_html/Shop/system/library/tax.php on line 31

Line 17 of tax.php: $this->setShippingAddress($address_query->row['country_id'], $address_query->row['zone_id']);

Line 31 of tax.php: $this->setPaymentAddress($address_query->row['country_id'], $address_query->row['zone_id']);