W3 Total Cache: Uncaught exception ‘Exception’ with message ‘unknown engine’

Error log contained the following message:

Uncaught exception ‘Exception’ with message ‘unknown engine ‘ in /wp-content/plugins/w3-total-cache/Cdnfsd_Core.php

After some researching I found this post that gave me a hint on how to resolve this issue.

To correct the problem you need to edit /wp-content/w3tc-config/master.php and change "cdnfsd.enabled": "1" to "cdnfsd.enabled": "0" and remove "cloudflare" property if it is available.

It appears that this problem occurs if plug-in is switched from Premium to Community mode with Cloudflare enabled.

MaAnna Stephenson from Blog Aid writes why she yanked W3 Total Cache off her recommended plugins list. According to MaAnna W3 Total Cache had stability issues last year, still in Beta and doesn’t receive attention it needs from the lead developer.

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  1. Dont cloudflare developers care about this stuff. This well known bug should have been fixed in an update. I am considering switching to WP Rocket, if I face one more problem.

  2. Thanks this post really helps me. I love W3 Total Cache plugin but many time it create so much complication. Do you know any better alternative which lightweight and creates no any complications?

  3. Hey Michael,

    I have been banging my head for this solution for almost 3 hours. You made my day.

    I don’t know how to thank you. I can only say you “thanks a lot”. May god bless you only good things in your life.

    Thanks again pal,
    Cheers :):):)

  4. This stuff is important to Do nt cloudflare developers. In an update, this popular bug should have been fixed. If I face another problem, I consider switching to WP Rocket.

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