I had this contriobution installed on a home computer for testing with xampp which uses apache, when I moved this site without any customers to a live server using iis6, PHP5 and mysql 5

Upon registering a test customer, I got a sql error about the column in customers not null, thus preventing the customer to being able to register.

To fix this,

1:> I fired up phpmyadmin, chose shop database on the left dropdown box then chose the table "customers" in the left column

2:> Now at the bottom in the main center window somewhere you should see customer_private_messages click on the change / pen symbol and where it says "not null" change to just "null"

Done!

This now fixes this problem.

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