Title: Cache/Preload now returns error
Last modified: April 30, 2020

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# Cache/Preload now returns error

 *  Resolved [ericbullet](https://wordpress.org/support/users/ericbullet/)
 * (@ericbullet)
 * [6 years, 1 month ago](https://wordpress.org/support/topic/cache-preload-now-returns-error/)
 * Cache/Preload now returns error[screen shot](https://drive.google.com/file/d/1uSKn8_jlxuheTXn4bUpToxayK-aQ6y6S/view?usp=sharing)
   
   function(){return f&&(c&&!b&&(h=f.length-1,g.push(c)),function b(c){n.each(c,
   function(c,d){n.isFunction(d)?a.unique&&j.has(d)||f.push(d):d&&d.length&&”string”!
   ==n.type(d)&&b(d)})}(arguments),c&&!b&&i()),this}

Viewing 12 replies - 1 through 12 (of 12 total)

 *  Plugin Support [bcrodua](https://wordpress.org/support/users/bcrodua/)
 * (@bcrodua)
 * [6 years, 1 month ago](https://wordpress.org/support/topic/cache-preload-now-returns-error/#post-12765247)
 * Hi,
 * This error indicates that something on the site is breaking JavaScript on the
   page, and causing JS code to be output.
 * Are you using any custom mu-plugins or drop-in plugins on the site?
    If so, I
   would recommend double checking their PHP and JS code.
 * If possible, please could you also try disabling the other plugins on the site,
   and try to run the preload again?
 * Does the error occur in this situation?
 * Best Wishes,
    Bryle
 *  [kazazor](https://wordpress.org/support/users/kazazor/)
 * (@kazazor)
 * [6 years, 1 month ago](https://wordpress.org/support/topic/cache-preload-now-returns-error/#post-12770715)
 * I’m getting this error as well. Not using any custom mu-plugins or drop-in plugins
   on the site.
    However, after I close this alert I do see the counter in the cache
   page goes up – so the preload seems to be working and just need to remove this
   message. Any idea what it could be?
 *  [uncharted](https://wordpress.org/support/users/lisaevans123/)
 * (@lisaevans123)
 * [6 years ago](https://wordpress.org/support/topic/cache-preload-now-returns-error/#post-12815043)
 * I’m getting the same error as well. The only mu-plugin is the ManageWP worker
   plugin. Please advise. I’ve got 30+ sites that are running with preload and they
   are all breaking with the same error that [@ericbullet](https://wordpress.org/support/users/ericbullet/)
   reported.
 *  [duriologist](https://wordpress.org/support/users/duriologist/)
 * (@duriologist)
 * [6 years ago](https://wordpress.org/support/topic/cache-preload-now-returns-error/#post-12865465)
 * I’ll chime in on this one. Sometimes it gives me the error box and sometimes 
   it doesn’t. I can’t find a cause for it.
 * Other than that, the caching works great!
    -  This reply was modified 6 years ago by [duriologist](https://wordpress.org/support/users/duriologist/).
 *  [duriologist](https://wordpress.org/support/users/duriologist/)
 * (@duriologist)
 * [6 years ago](https://wordpress.org/support/topic/cache-preload-now-returns-error/#post-12866184)
 * The preload seems to run despite the message box, though, just as [@kazazor](https://wordpress.org/support/users/kazazor/)
   said. I sat there and watched as the current cache size and number of files went
   right back up to what they should be.
 * I suspect the message box is a debugging aid for the programmer(s).
 * Thanks.
    -  This reply was modified 6 years ago by [duriologist](https://wordpress.org/support/users/duriologist/).
 *  Plugin Support [bcrodua](https://wordpress.org/support/users/bcrodua/)
 * (@bcrodua)
 * [6 years ago](https://wordpress.org/support/topic/cache-preload-now-returns-error/#post-12939001)
 * Hi,
 * We’ve just released a new version. Can you please update and see if you still
   get the same issue?
 * Best Wishes,
    Bryle
 *  [duriologist](https://wordpress.org/support/users/duriologist/)
 * (@duriologist)
 * [6 years ago](https://wordpress.org/support/topic/cache-preload-now-returns-error/#post-12939222)
 * I updated earlier this morning. The version I have is 3.1.2.
 * Now the Preload Now -> Run Now returns a message box with “An unexpected response
   was received.”
    -  This reply was modified 6 years ago by [duriologist](https://wordpress.org/support/users/duriologist/).
 *  [Marc Lacroix](https://wordpress.org/support/users/marcusig/)
 * (@marcusig)
 * [6 years ago](https://wordpress.org/support/topic/cache-preload-now-returns-error/#post-12942000)
 * Hi [@duriologist](https://wordpress.org/support/users/duriologist/)
 * Could you do the following:
    – Go to WP-Optimize > Cache – Open the developer
   tools (console) – Press the Preload Now -> Run Now button – In the network tab,
   follow the steps highlighted on the screenshot: ⌊screenshot⌉ – If the error shows
   again, press ok to discard it, and can you share the contents displayed in the“
   Response” tab?
 * Marc.
 *  [duriologist](https://wordpress.org/support/users/duriologist/)
 * (@duriologist)
 * [6 years ago](https://wordpress.org/support/topic/cache-preload-now-returns-error/#post-12944158)
 * Hi Marc,
 * I’m not sure this is what you’re looking for, but here’s what I got:
 * {“js”:[],”css”:[],”stamp”:”1591367074223″,”cachesize”:”0.00 B (0 files)”,”total_cache_size”:”
   19.55 MB (411 files)”,”cacheTime”:”June 3, 2020 @ 9:19 pm”,”cachePath”:”\/home1\/
   brainin2\/public_html\/wp-content\/cache\/wpo-minify\/1591233543\/assets”}
 * Please tell me if I got the wrong data for you.
 * Thanks,
 * Bryan
    -  This reply was modified 6 years ago by [duriologist](https://wordpress.org/support/users/duriologist/).
    -  This reply was modified 6 years ago by [duriologist](https://wordpress.org/support/users/duriologist/).
 *  [duriologist](https://wordpress.org/support/users/duriologist/)
 * (@duriologist)
 * [6 years ago](https://wordpress.org/support/topic/cache-preload-now-returns-error/#post-12944275)
 * Hi Marc,
 * Just as I said a couple of weeks ago, even though I got the message box, the 
   preload is again running anyway.
 * Thanks,
 * Bryan
    -  This reply was modified 6 years ago by [duriologist](https://wordpress.org/support/users/duriologist/).
 *  [Marc Lacroix](https://wordpress.org/support/users/marcusig/)
 * (@marcusig)
 * [6 years ago](https://wordpress.org/support/topic/cache-preload-now-returns-error/#post-12944358)
 * Hi Bryan,
 * Thanks. Yes I believe the preload is still triggered for most users.
    Though 
   it shouldn’t give an “unexpected response”.
 * The code you shared isn’t the right one (it’s part of the minify feature).
 * When choosing a “admin-ajax.php” in the list, in the headers’ form data, there
   should be “sub_action: run_cache_preload”, like highlighted on the screenshot.
 * Unfortunately, we haven’t been able to duplicate the issue in all our tests, 
   so it’s difficult to fix the issue once and for all.
 *  [duriologist](https://wordpress.org/support/users/duriologist/)
 * (@duriologist)
 * [6 years ago](https://wordpress.org/support/topic/cache-preload-now-returns-error/#post-12944759)
 * Hey Marc,
 * I keep getting “Unable to load response data”.
 * admin-ajax.php is in red letters in the left pane.
    -  This reply was modified 6 years ago by [duriologist](https://wordpress.org/support/users/duriologist/).

Viewing 12 replies - 1 through 12 (of 12 total)

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 * 12 replies
 * 6 participants
 * Last reply from: [duriologist](https://wordpress.org/support/users/duriologist/)
 * Last activity: [6 years ago](https://wordpress.org/support/topic/cache-preload-now-returns-error/#post-12944759)
 * Status: resolved