Zen Cart Upgrades
Ah, the wish for automatic upgrades! Sorry, folks, no such thing yet!
If you have used an automatic installer for Zen Cart, your hosting will tell you when it's time to upgrade. STOP! Don't click that button!
Have you installed any mods or made any changes to the original install? There's a very good possibility that automatic upgrade is going wipe out some or all of your changes. That's why we do Zen Cart site evaluations first. We find out what changes have been made and get the cart ready for upgrades. We find out what mods are going to have to be re-installed or that may no longer work before we touch anything.
There are presently 2 stable versions: Zen Cart 1.3.9h (note that "h" - anything else is not a stable, secure version) and Zen Cart 1.5. Many mods were not yet been upgraded for 1.5 - some may never be and you might be heavily relying on one of those mods right now.
Zen Cart 1.5 was done for one reason and one reason only: to get a PCI certified cart. Zen Cart is the only open source cart that is PCI certified. That took an outlay of money and lots of time for the Zen Cart core team to get it done. Many of you will really appreciate that if and when you find your cart being required to be compliant. Non-compliance means your merchant credit card processor will start charging you extra money each money. It could only be $20 a month but it also could be hundreds depending on the volume of your transactions.
The next upgrade is coming (1.5.3) soon by the way; we're just waiting for the PCI folks to finish the certification.