Fatal error: Allowed memory on /wp-includes/meta.php on line 838

While upping the memory limit can help, it’s most likely that your hosting plan doesn’t offer 512M, so that line won’t help here.

On the other hand, it might be best to look at what’s causing the memory issue before to add more memory. 236M is a lot. You should have enough with 64M on most single WordPress sites.

I’d suggest installing this plugin:
https://www.ads-software.com/plugins/debug-bar/

Then, start deactivating each one of your plugins, one at a time, and reviewing memory usage between each deactivation. You can check memory usage by clicking on the “Debug” button in the admin bar; memory usage will appear at the top of the page.

After deactivating each plugin, switch to one of the default themes, like Twenty Fifteen, for a few minutes. At that point, you should have a clear picture about which plugins eat up the most memory on your site. You can let the plugin authors know, they might be able to fix things for you.

I hope this helps.

PHP 7.0.2
MySQL 5.5.46
Memory Usage 12 128 776 bytes

Everything is normal except when I click on “My Jetpack”. But that does not matter ??

Thanks for your help ^^

Could you try to deactivate each plugin, one at a time, as I mentioned above, and let me know if the “My Jetpack” page becomes accessible after deactivating a specific plugin?

Thanks!

My site after updating to WP 4.5:

Fatal error: Allowed memory size of 134217728 bytes exhausted (tried to allocate 7680 bytes) in /var/sites/c/crackingjoe.uk/public_html/wp-admin/includes/import.php on line 37

I will look at your solution Jeremy and report back, probably Thursday.

O.o
?

Sometimes the trees hide the wood and the answer is right in front of you: WordPress update to 4.5 has overwritten wp-config.php and the memory limit is therefore 40m, son increase the memory limit by adding the line:

define( ‘WP_MEMORY_LIMIT’, ’96M’ );

See more here:
https://codex.www.ads-software.com/Editing_wp-config.php#Increasing_memory_allocated_to_PHP