How Can I Troubleshoot and Fix the '500 Internal Server Error' After Upgrading OpenCart to Version 4.0.0?

I recently upgraded my OpenCart store from version 3.0.3.8 to the latest stable release, 4.0.0, and after the upgrade, I started encountering a '500 Internal Server Error' when trying to load the front-end of my website. The admin panel is still working fine, but when I try to access the front-end, the error shows up. I’ve already tried a few things to resolve it, such as checking both the OpenCart error logs and the server logs, but they don’t seem to point to anything specific. I’ve also disabled all custom modules and themes to rule out compatibility issues, but the error persists. I made sure that the file and folder permissions are set correctly (755 for folders and 644 for files), but that didn’t help either. Has anyone else faced this issue after upgrading to OpenCart 4.0.0? If so, could you share what steps you took to troubleshoot or fix it? I’m also wondering if this could be related to PHP version compatibility or missing dependencies, or if there’s any database schema update required that I might have missed during the upgrade. I’m currently running PHP 7.4 on the server, and I didn’t have any major issues before the upgrade. Any help would be greatly appreciated!

I would post the full version of OpenCart you have upgraded to. The phrase "latest stable release" in meaningless when it comes to OpenCart 4.

You might want to just restore from your backup and then even upgrade to 3.0.4.0 in you want a more secure and stable release.

If you do want to persist with version 4 you will need to look in your server and PHP error logs, not just the OpenCart log, to see what is the cause of the error. Ask you host where to find these.

carolgrey98 wrote: ↑

Fri Nov 15, 2024 12:52 pm

I recently upgraded my OpenCart store from version 3.0.3.8 to the latest stable release, 4.0.0

As others have said, that probably wasn't the best thing you could have done. It would have been wiser to go to 3.0.4.0.

carolgrey98 wrote: ↑

Fri Nov 15, 2024 12:52 pm

a '500 Internal Server Error' when trying to load the front-end of my website.
<snip>
I’ve already tried a few things to resolve it, such as checking both the OpenCart error logs and the server logs

As others have said maybe you are not looking at the right server error log. 500 should have something in the server error log saying what is happening.

Mike

As above - OC4 is not stable enough for production sites.

That said, there is a discrepancy in what you are suggesting. OC4 can not be installed on php7.4, and since there is no OC version 4.0.0, it is unclear what you have done.

All that can be established from your post is that you have a general 500 Internal Server error, which from the error is an internal error from your server. It would not be possible for there to be nothing in your server log unless you have error logging suppressed.

Start again with your issue (and it would be helpful if you used line spacing - it is difficult to read and the obvious discrepancy above gets missed)

Re upgrading - and your question re any db schema changes - probably - this is why it is not advised to "upgrade" especially from a major version change, rather to install and use an import/export tool or do it yourself.

In addition, no mention of modules, themes etc, or the use of OCMOD, none of which are likely to work for OC4