Okay... don't be TOO intimidated. Last week I had trouble SPELLING "database", now I feel confident tinkering with them!
That thread, with the PATCH CODE that Dr Byte has written has to be inserted into your database.
What it will do is "modify" (or correct) the existing table structure that's causing your problem.
Now... you need to have PHPMYADMIN access to your database...
BEFORE YOU START - BACKUP YOUR SHOP AND DATABASE
If you DO have phpmyadmin, then log into phpmyadmin and you will see TWO frames on screen.
The LEFT frame asks you to select the database you want to work on.
(Select the appropriate database now, so it features in the right frame)
The RIGHT frame then displays your database and all the tables.
At the top of the RIGHT FRAME you will see a link called: SQL
Click that link
You now get a big INPUT box appear with the words "Run SQL Query" at the top and a GO button at the bottom right.
PASTE THIS CODE BELOW into that input box. Don't alter it in any way. It's the code Dr Byte has on that other thread:
truncate table query_builder;
INSERT INTO query_builder ( query_id , query_category , query_name , query_description , query_string ) VALUES ( '1', 'email', 'All Customers', 'Returns all customers name and email address for sending mass emails (ie: for newsletters, coupons, GV's, messages, etc).', 'select customers_email_address, customers_firstname, customers_lastname from TABLE_CUSTOMERS order by customers_lastname, customers_firstname, customers_email_address');
INSERT INTO query_builder ( query_id , query_category , query_name , query_description , query_string ) VALUES ( '2', 'email,newsletters', 'All Newsletter Subscribers', 'Returns name and email address of newsletter subscribers', 'select customers_firstname, customers_lastname, customers_email_address from TABLE_CUSTOMERS where customers_newsletter = '1'');
INSERT INTO query_builder ( query_id , query_category , query_name , query_description , query_string ) VALUES ( '3', 'email,newsletters', 'Dormant Customers (>3months) (Subscribers)', 'Subscribers who HAVE purchased something, but have NOT purchased for at least three months.', 'select c.customers_email_address, c.customers_lastname, c.customers_firstname from TABLE_CUSTOMERS c, TABLE_ORDERS o where c.customers_newsletter = '1' AND c.customers_id = o.customers_id and o.date_purchased < subdate(now(),INTERVAL 3 MONTH) GROUP BY c.customers_email_address order by c.customers_lastname, c.customers_firstname ASC');
INSERT INTO query_builder ( query_id , query_category , query_name , query_description , query_string ) VALUES ( '4', 'email,newsletters', 'Active customers in past 3 months (Subscribers)', 'Newsletter subscribers who are also active customers (purchased something) in last 3 months.', 'select c.customers_email_address, c.customers_lastname, c.customers_firstname from TABLE_CUSTOMERS c, TABLE_ORDERS o where c.customers_newsletter = '1' AND c.customers_id = o.customers_id and o.date_purchased > subdate(now(),INTERVAL 3 MONTH) GROUP BY c.customers_email_address order by c.customers_lastname, c.customers_firstname ASC');
INSERT INTO query_builder ( query_id , query_category , query_name , query_description , query_string ) VALUES ( '5', 'email,newsletters', 'Active customers in past 3 months (Regardless of subscription status)', 'All active customers (purchased something) in last 3 months, ignoring newsletter-subscription status.', 'select c.customers_email_address, c.customers_lastname, c.customers_firstname from TABLE_CUSTOMERS c, TABLE_ORDERS o WHERE c.customers_id = o.customers_id and o.date_purchased > subdate(now(),INTERVAL 3 MONTH) GROUP BY c.customers_email_address order by c.customers_lastname, c.customers_firstname ASC');
Then click "GO"
If you did everything correctly, that will fix the table that's required.
Log out of PHPMYADMIN (green exit button in left frame) and then see if your shop's working properly.
If not, RESTORE your backup.
