I've had recently an issue on my webshop which suddenly started frequently showing a 503 error which blocked my clients from accessing my website. With the help of my host they could narrow down that it was a plugin that consumed too much memory by getting stuck in a request loop when just loading my front page. The debug log showed that WPML was responsible for that. Since I deactivated WPML on my website it didn't crash anymore but I am not able to offer my clients their languages, nor can I use the plugin that I pay for (WMPL Multilingual CMS). Additionally due to this issue my website lost ranking and website visibility since then.
Please help to get WPML up and running again on my website since the deactivation broke my website structure and also lost online visibility. It's urgent!
2) Please enable debugging, replicate the issue, and check if there is any error in the debug.log file.
Here are the steps:
1. Enable WordPress debugging by editing your wp-config.php file. Add (or modify, if these lines already exist) the following lines before the comment /* That's all, stop editing! Happy publishing. */:
2. Replicate the error.
3. Check the debug.log file (located in the /wp-content/debug.log) for any WPML-related errors.
4. Copy and paste the full error message here.
Unfortunately I am not able to activate the plugin on the live website. Please find below an excerpt of the WP debug log. It might be good to know that when the plugin was still activated the website crashed seemingly random. sometime once and hour, sometimes 3x in 10 minutes. Thank you for your assistance!
[10-Dec-2025 12:10:28 UTC] PHP Fatal error: Allowed memory size of 2147483648 bytes exhausted (tried to allocate 20480 bytes) in /dom673642/wp-includes/class-wp-term-query.php on line 731
[10-Dec-2025 12:25:34 UTC] PHP Fatal error: Allowed memory size of 2147483648 bytes exhausted (tried to allocate 20480 bytes) in /dom673642/wp-content/plugins/sitepress-multilingual-cms/classes/utilities/class-debug-backtrace.php on line 133
[10-Dec-2025 12:25:35 UTC] PHP Fatal error: Allowed memory size of 2147483648 bytes exhausted (tried to allocate 245760 bytes) in /dom673642/wp-content/mu-plugins/object-cache-pro/src/Clients/Client.php on line 97
[10-Dec-2025 12:27:31 UTC] PHP Fatal error: Allowed memory size of 2147483648 bytes exhausted (tried to allocate 262144 bytes) in /dom673642/wp-content/plugins/sitepress-multilingual-cms/vendor/wpml/fp/core/Strings.php on line 79
[10-Dec-2025 12:27:32 UTC] PHP Fatal error: Allowed memory size of 2147483648 bytes exhausted (tried to allocate 262144 bytes) in Unknown on line 0
[10-Dec-2025 12:29:58 UTC] PHP Fatal error: Allowed memory size of 2147483648 bytes exhausted (tried to allocate 20480 bytes) in /dom673642/wp-includes/functions.php on line 4953
[10-Dec-2025 12:31:55 UTC] PHP Fatal error: Allowed memory size of 2147483648 bytes exhausted (tried to allocate 20480 bytes) in /dom673642/wp-includes/class-wp-term-query.php on line 731
[10-Dec-2025 12:32:25 UTC] PHP Fatal error: Allowed memory size of 2147483648 bytes exhausted (tried to allocate 20480 bytes) in /dom673642/wp-includes/class-wp-term-query.php on line 731
[10-Dec-2025 13:00:57 UTC] PHP Deprecated: ltrim(): Passing null to parameter #1 ($string) of type string is deprecated in /dom673642/wp-includes/formatting.php on line 4486
[10-Dec-2025 13:07:45 UTC] PHP Deprecated: ltrim(): Passing null to parameter #1 ($string) of type string is deprecated in /dom673642/wp-includes/formatting.php on line 4486
[10-Dec-2025 13:07:45 UTC] PHP Deprecated: ltrim(): Passing null to parameter #1 ($string) of type string is deprecated in /dom673642/wp-includes/formatting.php on line 4486
[10-Dec-2025 13:33:26 UTC] PHP Fatal error: Allowed memory size of 2147483648 bytes exhausted (tried to allocate 20480 bytes) in /dom673642/wp-includes/class-wp-term-query.php on line 731
[10-Dec-2025 14:08:12 UTC] PHP Deprecated: ltrim(): Passing null to parameter #1 ($string) of type string is deprecated in /dom673642/wp-includes/formatting.php on line 4486
[10-Dec-2025 14:08:13 UTC] PHP Deprecated: ltrim(): Passing null to parameter #1 ($string) of type string is deprecated in /dom673642/wp-includes/formatting.php on line 4486
[10-Dec-2025 14:21:51 UTC] PHP Fatal error: Allowed memory size of 2147483648 bytes exhausted (tried to allocate 262144 bytes) in /dom673642/wp-content/plugins/sitepress-multilingual-cms/vendor/wpml/fp/core/functions.php on line 139
[10-Dec-2025 14:21:52 UTC] PHP Fatal error: Allowed memory size of 2147483648 bytes exhausted (tried to allocate 262144 bytes) in Unknown on line 0
[10-Dec-2025 14:31:56 UTC] PHP Fatal error: Allowed memory size of 2147483648 bytes exhausted (tried to allocate 20480 bytes) in /dom673642/wp-includes/functions.php on line 4953
[10-Dec-2025 14:32:26 UTC] PHP Fatal error: Allowed memory size of 2147483648 bytes exhausted (tried to allocate 262144 bytes) in /dom673642/wp-content/plugins/sitepress-multilingual-cms/vendor/wpml/fp/core/Strings.php on line 79
[10-Dec-2025 14:32:27 UTC] PHP Fatal error: Allowed memory size of 2147483648 bytes exhausted (tried to allocate 262144 bytes) in Unknown on line 0
[10-Dec-2025 14:39:38 UTC] PHP Fatal error: Allowed memory size of 2147483648 bytes exhausted (tried to allocate 20480 bytes) in /dom673642/wp-includes/functions.php on line 4953
[10-Dec-2025 14:41:32 UTC] PHP Fatal error: Allowed memory size of 2147483648 bytes exhausted (tried to allocate 20480 bytes) in /dom673642/wp-includes/functions.php on line 4953
[10-Dec-2025 14:41:34 UTC] PHP Fatal error: Allowed memory size of 2147483648 bytes exhausted (tried to allocate 20480 bytes) in /dom673642/wp-includes/functions.php on line 4953
[10-Dec-2025 14:51:07 UTC] PHP Fatal error: Allowed memory size of 2147483648 bytes exhausted (tried to allocate 262144 bytes) in /dom673642/wp-content/plugins/sitepress-multilingual-cms/vendor/wpml/collect/src/Illuminate/Support/Traits/Macroable.php on line 51
[10-Dec-2025 14:51:08 UTC] PHP Fatal error: Allowed memory size of 2147483648 bytes exhausted (tried to allocate 262144 bytes) in Unknown on line 0
I can see the following error coming from different plugins:
PHP Fatal error: Allowed memory size of 2147483648 bytes exhausted (tried to allocate 245760 bytes)
This indicates that the server is running out of memory and is triggering a fatal error.
Could you please let me know:
• Do you notice any specific action that triggers this error (for example, opening a particular page, saving changes, or running a specific process)?
• Are you currently unable to activate WPML because of this error?
Additionally, please share a screenshot of Tools → Site Health → Info → Server. This information will help me better understand your server environment and identify potential limitations.
After this issue occurred, I have been in contact with my host as I reckoned a memory issue. The memory has been increased to 2GB to see if it solved the issue. Unfortunately no success. Their technical team investigated a bit further and concluded that a plugin was causing this issue. The debug log revealed that wpml caused the time-outs:
[10-Dec-2025 12:27:31 UTC] PHP Fatal error: Allowed memory size of 2147483648 bytes exhausted (tried to allocate 262144 bytes) in /dom673642/wp-content/plugins/sitepress-multilingual-cms/vendor/wpml/fp/core/Strings.php on line 79
[10-Dec-2025 14:21:51 UTC] PHP Fatal error: Allowed memory size of 2147483648 bytes exhausted (tried to allocate 262144 bytes) in /dom673642/wp-content/plugins/sitepress-multilingual-cms/vendor/wpml/fp/core/functions.php on line 139
[10-Dec-2025 14:32:26 UTC] PHP Fatal error: Allowed memory size of 2147483648 bytes exhausted (tried to allocate 262144 bytes) in /dom673642/wp-content/plugins/sitepress-multilingual-cms/vendor/wpml/fp/core/Strings.php on line 79
[10-Dec-2025 14:51:07 UTC] PHP Fatal error: Allowed memory size of 2147483648 bytes exhausted (tried to allocate 262144 bytes) in /dom673642/wp-content/plugins/sitepress-multilingual-cms/vendor/wpml/collect/src/Illuminate/Support/Traits/Macroable.php on line 51
There was no obvious trigger that caused the server error. I have a website monitoring software that notified me whenever the site was down. When the website was working then it had incredibly high loading times - if it was loading too long the server error occurred. Usually it took 5-10 minutes and then the website was working again with very slow loading times until the error happened again.
When activating the WMPL plugin on the live website it will increase the loading times significantly and cause it to crash at some point. Therefore I can't activate it safely. Once I deactivated WMPL my website hasn't experienced any crashes anymore.
Your server limits look sufficient, so this does not appear to be a general resource issue.
However, the logs indicate that object-cache-pro may be caching incorrect data:
[10-Dec-2025 12:25:35 UTC] PHP Fatal error: Allowed memory size of 2147483648 bytes exhausted
in /wp-content/mu-plugins/object-cache-pro/src/Clients/Client.php on line 97
There is also a related error involving taxonomy terms:
[10-Dec-2025 12:10:28 UTC] PHP Fatal error: Allowed memory size of 2147483648 bytes exhausted
in /wp-includes/class-wp-term-query.php on line 731
Based on this, I suspect that deactivating object-cache-pro while activating WPML would also prevent the issue from occurring.
Please try the following:
1. Clear all caches
• Server cache
• Site cache
2. Go to object-cache-pro settings and add the following to DO NOT CACHE GROUPS:
counts
plugins
themes
terms
3. Save the settings.
4. Activate WPML and test again.
Upcoming fix in WPML 4.9
Some fixes related to object caching are already included in WPML 4.9 (currently beta):
• Fixed an issue where deleted strings were not re-added after rescanning.
• Fixed an infinite recursion issue when translating taxonomy terms.
I've tried to follow your instructions but unfortunately I got stuck finding out that the caching plugin is a native and mandatory plugin from my host. I have no access to settings or any other details and I also have no option of deactivating it.
What do you suggest in this case?
Do I understand correctly that you don’t have access to this plugin’s settings in the WordPress dashboard?
There should normally be settings available, as shown in the attached screenshot.
If the settings are still unavailable, testing with the beta versions of the WPML plugins would be the next step. Unfortunately, beyond that, I don’t have any other recommendations.
