Web Design | SEO | Website Development

Search Engine Optimisation, Magento & Wordpress Specialist [Cranleigh | Surrey]

Magento Extension Installation Fatal error: Don’t Panic!

By In Advice, Platforms, Website Development On 10/03/2012

When installing a Magento extension if you get a nasty error after installation (when going to System | Configuration) that looks something like this:

Fatal error: Class ‘THE EXTENSION’ not found in /public_html/app/Mage.php on line 516


  • The reason is that your complier is enabled…
  • The solution is to uninstall the extension you’ve just installed using your Magento Connect Manager then go you System | ToolsCompilation, then disable the Complier. Reinstall the extension and then once it’s all working re-enable your complier.

It is best practice to always disable the complier when installing extensions and then re-enabling it once installation is completed.

Hope this helps someone!

About the Author

Dan Vince

Yet another Web Development Professional

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  • Mark Harley 8 YEARS AGO

    Lifesaver dude! Thanks, I have been pulling my hair out all day

  • Dan Vince 8 YEARS AGO

    Hey no worries! I'm just glad someone out there finds my ramblings useful.


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