Quote Originally Posted by stevesh View Post
It's most likely your PHP version. Zencart 1.3.X isn't compatible with PHP 5.4 and up. There's no patch I'm aware of. This is another good (vital, even) reason to upgrade your Zencart store as each upgrade becomes available.
Nodding in agreement. Upgrade suggested.

There are many others that have been in the same situation reporting the same results and have had to take the same action described by stevesh. Please follow the guidelines posted in the FAQ, officially posted elsewhere on this site, or the documents of the downloaded version of ZC available from http://www.zen-cart.com/getit. On performing the upgrade, please follow each step, carefully, and continue to ask questions as necessary in the appropriate thread(s).