[Plugin: Hide Login] Error in active plugin

I receive this notice when I active the plugin:

Notice: Undefined index: action in D:\xampp\htdocs\truequebook\wp-content\plugins\hide-login\hide-login.php on line 36

Some help on it?.

I think that this is not an error, but a notice, but at the end, the plugin does not active.

Thank you

http://wordpress.org/extend/plugins/hide-login/