HTML migration error code

Beta
#1

I copied my site over to a staging site, wanting to test the HTML migration. MOre or less immediately it spit out the following error message:

{“readyState”:4,“responseText”:“

There has been a critical error on this website.

<a href=“https://wordpress.org/documentation/article/faq-troubleshooting/”>Learn more about troubleshooting WordPress.

”,“status”:500,“statusText”:“error”}

I will add a secure not with login-credentials to the staging site. Feel free to play with it.

#2

I had the exact same thing on my staging site. My problem was that i switched on the maintenance mode directly in the hosting panel. After deactivating it there and tunring on a maintenance plugin everything worked.

#3

@striata Can you turn on WP_DEBUG on that site? Or let me know where the debug log is there. I can diagnosis from there. You can also try what deranaloge said as well. Have a great day.

#4

I there an update on this issue? I have the exact same problem on RC1.

#5

@xoa Create a new thread where I could see the site. Or enable WP_DEBUG and let me know the message you received. Have a great day.

#6

Tried again with the .1 stable release: Pushed the site over to staging, updated Pro, and tried the “Migrate to HTML”. Immediately got the following error:
image I then de-activated plugins, a bunch of plugins at a time. At one point, migration worked for 29 pages, and on the 30th page, got the same error message again. I kept de-activating plugins, until any and all plugins were deactivated. It is still stalling at the 30th page.
I do not know how to “turn on WP_DEBUG”, and I do not know where to find logs. The login-in credentials in the secure note above are still valid for the staging site. The current state of the staging site is with all plugins disabled.

#7

There’s a guide here. You can also send FTP info. I can prevent the “undefined” message, but I would still need the site in debug mode to see what the actual error is. Thanks for sending this my way.

https://support.cloudways.com/en/articles/8694124-how-to-enable-wordpress-debug-mode

#8

@charlie I am having the same or at least a similar issue. I have a site with WPML that I moved from a live server to a local development environment as one of our imports has gone weird recently. (I used Updraft Plus Pro for the migration of the DB). I needed to test a few things and thought I may as well test and migrate the development site to HTML Storage.

The site in question was upgraded from 6.5.16 to 6.6.1.

The PHP error I am seeing is this.

[05-Mar-2025 06:10:49 UTC] PHP Fatal error: Uncaught TypeError: call_user_func_array(): Argument #1 ($callback) must be a valid callback, class SaveFont_CCIcons does not have a method “cs_document_storage_migrate” in /var/www/xxxxxx/public_html/wp-includes/class-wp-hook.php:324
Stack trace:
#0 /var/www/xxxxxx/public_html/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters()
#1 /var/www/xxxxxx/public_html/wp-includes/plugin.php(517): WP_Hook->do_action()
#2 /var/www/xxxxxx/public_html/wp-admin/admin-ajax.php(192): do_action()
#3 {main}
thrown in /var/www/xxxxxx/public_html/wp-includes/class-wp-hook.php on line 324

#9

@urchindesign It sounds like some plugin issue. I’m not sure where SaveFont_CCIcons is from, but it’s not from Cornerstone or our extensions. It sounds like it is hooking into every admin ajax command and not doing it properly. This isn’t some old version of PHP right?

#10

My bad, but at least you put me in the right direction.

As the site is slightly older I am using the plugin Cornerstone Custom Icons built by Michael.

Perhaps it isn’t compatible with the migration. I’m going to see if I can get rid of the plugin and see if the migration works.

#11

@charlie I’m going to open a new ticket.

#12

Here is an update on my HTML migration problem.

Step 1:

  • On the staging site, with ALL plugins de-activated, migration started, but stalled on the 30th page (as already reported above)
  • I managed to activate WP_DEBUG. The error message pointed to a line in functions.php. On that line, I had a custom looper set up for ACF.
  • I re-activated ACF, and the migration was successful.

Step 2:

  • I pushed the live site over to staging again, starting from scratch.
  • HTML migration did not work, same as reported above (the ‘undefined’ error)
  • I have checked the error log. There were messages related to the WP Rocket plugin and the Complianz plugin. I de-activated both.
  • Migration still does not work, but there is only a single error message left in debug.log:

[06-Mar-2025 16:54:05 UTC] PHP Fatal error: Allowed memory size of 314572800 bytes exhausted (tried to allocate 131072 bytes) in /home/xxx.cloudwaysapps.com/xxx/public_html/wp-includes/class-wpdb.php on line 2316

  • I then tried to deactivate, and re-activate, each plugin one at a time, but I never got migration to work.
#13

Based on that response, we’ll probably need to improve the memory on the migration. Your site is probably to big to run the current migration. We should have an update in the next release. Have a great day.