Title: Missing file autoptimize_fallback.css
Last modified: November 17, 2023

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# Missing file autoptimize_fallback.css

 *  Resolved [romaniglin](https://wordpress.org/support/users/romaniglin/)
 * (@romaniglin)
 * [2 years, 6 months ago](https://wordpress.org/support/topic/missing-file-autoptimize_fallback-css/)
 * I’m using the “Enable 404 fallbacks” option and I’m going to add the setting 
   to the Nginx file, but I couldn’t find the file ‘autoptimize_fallback.css’ in
   the /wp-content/cache/autoptimize/1/css/ folder (this is a multisite). At the
   same time, the file autoptimize_fallback.js is present in the /wp-content/cache/
   autoptimize/1/js/ folder.
 * 
   WordPress 6.4.1Autoptimaze 3.1.10WPengine hosting.
 * Any ideas? Thanks
 * The page I need help with: _[[log in](https://login.wordpress.org/?redirect_to=https%3A%2F%2Fwordpress.org%2Fsupport%2Ftopic%2Fmissing-file-autoptimize_fallback-css%2F%3Foutput_format%3Dmd&locale=en_US)
   to see the link]_

Viewing 5 replies - 1 through 5 (of 5 total)

 *  Plugin Author [Optimizing Matters](https://wordpress.org/support/users/optimizingmatters/)
 * (@optimizingmatters)
 * [2 years, 6 months ago](https://wordpress.org/support/topic/missing-file-autoptimize_fallback-css/#post-17210595)
 * the fallback files are only created when “aggregate” is on romaniglin, so if 
   you want to be able to rely on the fallbacks you’ll have to (consider) to aggregate
   the CSS (and JS).
 * I have an item on my backlog to somehow take care of missing files when “aggregate”
   is off but (a) it’ll require a change in how/ where autoptimized files are stored
   but fortunately (b) the impact of missing files when not aggregating is typically
   a lot smaller.
 * hope this clarifies,
    frank
 *  Thread Starter [romaniglin](https://wordpress.org/support/users/romaniglin/)
 * (@romaniglin)
 * [2 years, 6 months ago](https://wordpress.org/support/topic/missing-file-autoptimize_fallback-css/#post-17211043)
 * Thanks for the quick response. It really started to generate autoptimize_fallback.
   css after I enabled aggregation for CSS files.
   If I change the file name for 
   generated autoptimize_2efe….css in the inspector, redirecting to the autooptimize_fallback.
   css file starts working.To clarify, Do I need to add settings for nginx in this
   case, or does it work as it should?
 * Thanks
    -  This reply was modified 2 years, 6 months ago by [romaniglin](https://wordpress.org/support/users/romaniglin/).
 *  Plugin Author [Optimizing Matters](https://wordpress.org/support/users/optimizingmatters/)
 * (@optimizingmatters)
 * [2 years, 6 months ago](https://wordpress.org/support/topic/missing-file-autoptimize_fallback-css/#post-17211413)
 * if the redirection works in your test, changes in nginx are indeed not needed
   any more.
 *  Thread Starter [romaniglin](https://wordpress.org/support/users/romaniglin/)
 * (@romaniglin)
 * [2 years, 6 months ago](https://wordpress.org/support/topic/missing-file-autoptimize_fallback-css/#post-17211915)
 * Resolved. Thank you!
 *  Plugin Author [Optimizing Matters](https://wordpress.org/support/users/optimizingmatters/)
 * (@optimizingmatters)
 * [2 years, 6 months ago](https://wordpress.org/support/topic/missing-file-autoptimize_fallback-css/#post-17211966)
 * you’re welcome, feel free to [leave a review of the plugin and support here](https://wordpress.org/support/plugin/autoptimize/reviews/#new-post)!
   🙂

Viewing 5 replies - 1 through 5 (of 5 total)

The topic ‘Missing file autoptimize_fallback.css’ is closed to new replies.

 * ![](https://ps.w.org/autoptimize/assets/icon-256X256.png?rev=2211608)
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 * 5 replies
 * 2 participants
 * Last reply from: [Optimizing Matters](https://wordpress.org/support/users/optimizingmatters/)
 * Last activity: [2 years, 6 months ago](https://wordpress.org/support/topic/missing-file-autoptimize_fallback-css/#post-17211966)
 * Status: resolved