In WordPress Fatal Error: Out Of Memory (Allocated xx…) (Tried To Allocate xx…) Bytes comes when certain PHP scripts require more than the default given memory in PHP.
The issue can be resolved by using following method suggested by Samboll (WP Forums Moderator):
Method 1: Open your wp-config.php file and add the following line
Method 2: You can edit the following line in your PHP.ini file
If your line shows 32M try 64M
memory_limit = 64M ;
Maximum amount of memory a script may consume is (64MB)
Method 3: If you don’t have access to your PHP.ini then try adding following line to .htaccess file:
php_value memory_limit 64M
OR, Talk to your hosting provider.