Increase Maximum Execution Time for WordPress – You may receive a message such as “Maximum execution time of 60 seconds exceeded” or “Maximum execution time of 60 seconds exceeded” for WordPress. This means that it is taking too longer for a process to complete and it is timing out. There are a number of ways to fix this error.
Option 1: Edit file wp-config.php:
Add the following to wp-config.php:
Option 2: Edit file .htaccess:
Make sure you back up .htaccess before you edit it.
Add the following to .htaccess:
php_value max_execution_time 600
Option 3: Editing php.ini
Add the following to php.ini:
max_execution_time = 600