Zen Cart v1.3.x and higher have better support for MySQL5 than prior versions did.

However, it is not officially supported.

You will find that if your host configures their MySQL5 such that STRICT_TRANS_TABLES is disabled, things will work without issue.

http://www.zen-cart.com/forum/showthread.php?t=37597
http://www.zen-cart.com/forum/showth...t=23628&page=2


In MySQL configuration menus: Startup Variables / Advanced /SQL Mode
Disable/delete the option STRICT_TRANS_TABLES