Michael Ott

It’s often too easy to make edits to your web site that result in a broken link. This plugin will automatically email the web site administrator (or a specified email address) whenever a 404 is encountered, along with a link to the page the 404 originated from. With this knowledge in hand, you can search the page for the problem and either remove or fix it.
Notifications are also triggered by missing media, such as images, video, CSS files and more.
<h3>Support</h3>
Report any issues at the official <a href="https://wordpress.org/support/plugin/404-notify/" rel="ugc">404 Notify Support</a> WordPress page.
<h3>How to use</h3>
Once activated, notifications are automatially sent to the site administrator, or, you can specify an alternative email address in Settings -> General and look for the 404 Notify email address field.
<h3>Uninstall</h3>
Deactivate the plugin, delete if desired.

404 Notify

It works as presented. When an internal link leads to 404 you get an email alert. 

Job well done

Get a notification whenever a 404 is encountered on your web site.

manojtd

<blockquote>
Sunset Edition 
 This update of the plugin is the last publicly released version. We do not expect to make any serious changes or add new features to it from now on.
We may not always be able to provide prompt support for this plugin on the WordPress.org forums. If you would like to have professional support or extra/custom features, consider buying the <a href="http://buy.thulasidas.com/plugin-check" title="Plugin Check to detect undefined functions and methods, $5.95" rel="nofollow ugc">Pro version</a>.
</blockquote>
Plugin Check is a developer tool. It scans the plugin or application you specify (or upload) and determines whether you have undefined functions or methods in it.
PHP is not a compiled language. It looks for functions during runtime. So if you have a segment of code not covered by your normal testing, and you have an undefined function in there, you will never know of the undefined function until it hits production when the particular conditions activating that particular code segment are met. This tool will prove especially useful during large scale refactoring, or for quality checking for submission to sites like CodeCanyon.
<blockquote>
Live Demo
Plugin Check has a beautifully designed admin interface, which is feature-rich, user-friendly and functional. Please visit this fully operational <a href="http://demo.thulasidas.com/plugin-check" title="Play with Plugin Check Pro" rel="nofollow ugc">live demo site</a> to see it in action.
</blockquote>
Now available in your language using Google Translate.
<h4>Features</h4>
<ul>
<li>Ability to Validate Plugins: Plugin Check can detect undefined functions and methods in your plugin.</li>
<li>Modern Admin Interface: Plugin Check sports a modern and beautiful admin interface based on the twitter bootstrap framework. Fully responsive.</li>
<li>Admin Interface Tour: A slick tour will take you around the admin page and familiarize you with its features.</li>
<li>Generous Help: Whenever you need help, the information and hint is only a click away in Plugin Check. (In fact, it is only a mouseover away.)</li>
<li>Standalone Mode: Plugin Check works as a WordPress plugin if uploaded to the <code>wp-content/plugins</code> folder of your blog, or as a standalone application if uploaded to your server. What’s more, you can switch to the standalone mode from the WordPress plugin admin page of this plugin, while still using the WordPress authentication mechanism and database.</li>
</ul>
<h4>Pro Version</h4>
In addition to the fully functional Lite version, Plugin Check also has a <a href="http://buy.thulasidas.com/plugin-check" title="Plugin Check to detect undefined functions and methods, $5.95" rel="nofollow ugc">Pro version</a> with many more features. These features are highlighted by a red icon in the menus of the lite version.
<ul>
<li>Upload and Check PHP packages: In the Pro version, you can upload a plugin or a package as a zip file and check for missing function/method definitions.</li>
<li>Automated Checks: With the Pro version, you can run a suite of checks (adapted and further developed from the excellent Theme Check plugin) on the plugin as well.</li>
<li>WordPress Aware: The Pro version is aware of WordPress functions and their deprecation status. It also knows the common global variables in WordPress.</li>
<li>Skinnable Admin Interface: In the Pro version, you can select the color schemes of your admin pages from nine different skins.</li>
<li>Advanced Options: The Pro version lets you configure advanced options like suppressing duplicates, displaying all detected tokens etc.</li>
<li>Execution Parameters: Ability to specify the maximum execution time and memory size for large compilation jobs.</li>
</ul>

Plugin Check

Pro version is great!
It's worth every penny + Manoj quick with his help too.
Thank you so much!



Pro version is great!

Pretty good design. The results are aren't very clear though. No need to show the "The auto-generated code is:" section. With a little more work this could be great.



Pretty good.

Not working.

Plugin Check is a validation tool for PHP developers (and a quality checker for end users) to locate undefined functions and methods.

404 Notify vs Plugin Check