You can fix custom field save issue in dashboard by increasing ‘PHP max input variables’ size and ‘PHP post max size’. If you have more fields , increase the value around 5k for ‘PHP max input variables’ and 256M for ‘PHP post max size’.
PHP max input variables & PHP post max size
The max_input_vars & post_max_size directive can be set in
wp-config.php file. To gain access to these files you will need FTP credentials. If you do not have these please contact your hosting provider.
- In your WordPress root installation locate any of these
- Edit the file and paste the directive code
- Once you are done making changes save the file. If you have downloaded the file to make this change, upload it back to your server and override the existing file.
Directive for .htaccess
php_value max_input_vars 5000 php_value post_max_size 256M
Directive for php.ini or .user.ini
max_input_vars =5000 post_max_size = 256M
Directive for wp-config.php
@ini_set( 'max_input_vars' , 5000 ); @ini_set( 'post_max_size', '256M');
If this limit is not word then you need to increase the limit more (Depend on your custom field list)
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