About PHP versions

Zen Cart® v1.5.6 is designed for PHP 5.6 to 7.3, with MySQL 5.1 to 5.7 (or MariaDB 10.0-10.2) and Apache 2.2/2.4

While it is compatible with PHP 5.4.9 through PHP 7.3 for backward-compatibility while upgrading your site, you should be using a newer version whenever possible. As of the time of writing this, PHP 5.6 is considered obsolete. and you should be using PHP 7.1 or greater.

Upgrade Instructions

This document only mentions the actual changes specific to v1.5.6 since v1.5.5.

From v1.5.5

If you are already using v1.5.5 and *have NOT customized or altered* any of the files listed in the changed_files-v1-5-6.html document, then simply replace those files with the new files as listed.

If you have *have customized or altered* certain files, simply re-do your customizations in the new version of those particular files by making the same changes needed.

If you are using Addons/Plugins that have made alterations to those files, it is best to compare those changed files against the original Zen Cart files for the version those plugins were built for, and see what changes were there ... and then re-build those changes in the v1.5.6 file.

To v1.5.6 from v1.5.4 or older

If you are upgrading from a version OLDER than v1.5.5, then please do a standard site upgrade. Be sure to review all the links in this article, including tips on staging the upgrade in a separate directory/folder.

CHANGELOG - List of Changed Files

For a list of files that have been changed since v1.5.5, see the changed_files-v1-5-6.html document.

A Note About Upgrading to the New Responsive Classic Template Added in v1.5.5

While Zen Cart® v1.5.5/v1.5.6 contains a newer "responsive_classic" template, we STRONGLY recommend that upgraders first upgrade the site using everything (including template_default) EXCEPT the contents of responsive_classic template.

Then once the upgraded site is working properly you can consider what changes you might want to make to your own active template.

(Important notes about template_default are shown below)

AGAIN: The responsive_classic template should NOT be implemented immediately as part of an upgrade; it should be a separate step ... if it is even used at all.

It is not NECESSARY to use responsive_classic ON YOUR EXISTING SITE, and you should UPGRADE THE REST OF YOUR SITE FIRST before attempting to convert/adapt it for use.

Upgrader Notes About Changes to template_default

Upgraders should make sure they update *BOTH* template_default *AND* their custom templates as described here

In Zen Cart the template_default directory contains the master copy of all storefront page templates.

The normal procedure for customizing template files for use in your own personalized template is to make a copy of the corresponding file from template_default, put it into your own template folder (and matching folder structure), and make your customizations in that copy of the file.

This way the only files you need in your personalized template folder are those that you have altered in some way from template_default.

With that explained, it is important that whenever you upgrade your site, you should also inspect ALL the template_default files to determine which changes in those files need to be replicated in your customized files.

Often a tool like Beyond Compare or Araxis Merge or GnuDiff can be helpful for this.

The process is simple: compare the template_default directory files from your *old* version against the template_default files in the *new* version, and use those results as a reference to copy those updated changes into each of the files you have customized in your custom/personalized template in your store.

Then, and only after you have done all those comparisons and updated your customized files in your custom template folder, you will copy the template_default files from the new version into the template_default directory of your store. This way you will be left with updated personalized files *and* updated template_default files.

This way you will be left with updated personalized files *and* updated template_default files.