The wordpress redirection plugin allow control over missing url.
When you change a post URL it automatically keeps track of that and it creates a new rule to redirect the old address to the new one.
It also very usefull to redirect deleted pages somewhere else.
It has a loggin system to keep track of every 404 error so you can add rule directly from the plugin without going to check the server logs or the webmaster tools.
Once installed go in “Tools > Redirection” to configure it, expecially the “Apache” modules needs to be instructed about the server path where .htaccess can be found.
In the “Options” pages make also sure to turn on the checkbox for the “Post & Page URLs: – Monitor new posts” option.no more 404 errors with the Redirection wordpress plugin,