Hi,
It seems memory limit issue. Methods for increasing the amount of memory a PHP script may consume
1. If you have access to your install and are running a version of WordPress earlier than 3.0, try the plugin
http://wordpress.org/extend/plugins/memory-bump/ as this is the easiest way to increase your RAM for WordPress.
2. If you have access to your PHP.ini file, change the line in PHP.ini
If your line shows 32M try 64M. If your line shows 64M try 128M
memory_limit = 64M ; Maximum amount of memory a script may consume (32MB)
3. If you don’t have access to PHP.ini try adding this to an .htaccess file:
php_value memory_limit 64M
4. Try adding this line to your wp-config.php file:
Increasing memory allocated to PHP
define('WP_MEMORY_LIMIT', '64M');
5. Talk to your host.
After that try to activate the plugin. Hope it should help to you.
Thanks
Mohammad
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