Strange behaviour on plugin and update page

Hi, When I try to update the plugin using the WordPress Update page, it gets stuck on this page

When I reload the page, the plugins are updated, can you help me?

  • Adam Czajczyk

    Hi Mike D

    I hope you're well today and thank you for your question!

    I have checked your site and I honestly admin I'm quite stumped. I can see the issue there and it looks like the update itself seems to be running fine but just the info is not updated on the site.

    However, there's no errors in a browser console, no debug.log gets created, no PHP error_log, basically nothing that could give a clue why this is happening. There's also no "strange"/suspicious files in your WP install, file/folder permissions look fine, .htaccess is perfectly fine too...

    My bet here would be that something's breaking/blocking some admin-ajax request or some JS while that update is performed but I must say I'm not sure what and I'm not entirely sure if this is a right "shot".

    I've included our developers in the case so they could take a look into it. I've passed all the information to them along with an FTP credentials for staging site (please make sure that support access to the staging site is kept active - it's time valid so do not let it expire before they have a chance to check it, please) and hopefully they'll be able to spot what I have missed and solve that "riddle".

    Keep an eye on this ticket for further information, please.

    Best regards,

  • Adam Czajczyk

    Hi Mike D

    Hm... you might actually be right but truth to be said, I'm not quite sure what to look in the database for if it comes to this specific issue, especially taking into account that updates via plugins list seem to be working fine. One thing that comes to my mind might be something related to transient but then - clearing it (which I just did using Hummingbird) doesn't help and I don't think there's much else that could be done regarding it.

    But I've already added your suggestion to the report I created for our developers so they'd check that too. One more thing that comes to my mind is also a "caching issue": are there any server-side caches? I can't tell since I don't have any access to the server but it would also be great if you could provide such access (it would also let us check the databse). Please don't post it on forum but instead you can just put it in a text box (on a staging site) under the "Access granted" button on "WPMU DEV -> Support" page in your site's back-end. Just let me know here once it's there, please :slight_smile:

    Best regards,

  • Mike D

    Thank you guys!

    Well, the update page and updating plugins seems to working fine again. I am still having some strange issues, hard to tell where its coming from. Today I found out my LAN has been DNS highjacked and I cant login to my website via FTP. I dont know if there is any relation between all these bloody issues happening at once but its safe to say that this thread can be closed. Im going to hide under a rock for a bit.

  • Konstantinos Xenos

    Hey Mike D ,

    I see that from another ticket you've given us access to your CPanel so I want to ask for permission to create a local copy of your site on my test servers to try and figure out what might be going on with your core-update.php. This might even be a ticket for Core as well as I don't see anything wrong with all the 'known' issues for the time being.

    Inform me if that's ok and I'll get back to you as soon as possible with any findings.


  • Konstantinos Xenos

    Hey Mike D !

    Yes of course I delete them ( they are already deleted as I want my servers clean as well either way - in any case I was testing locally as well so no need to worry about anything ).

    To our issue.

    I've finally found out what was wrong after a lot of digging since I couldn't replicate on my end so I'll explain and you do as you think it's better for your setup since I don't know all of your plugins etc.

    WordPress by default doesn't play well with zlib.output_compression and it was enabled for your setup.

    Since that was enabled but it errors out 'early' there was no error in your .logs but this is what was actually happening when the update process was ongoing

    Notice: ob_end_flush(): failed to send buffer of zlib output compression (0) in /home/squarefe/public_html/wp-includes/functions.php on line 3743

    After that error WP couldn't continue the process to 'inform' you that everything was actually fine.

    I've disabled the zlib.output_compression for the time being since 'usually' it's better to have it to Off for WordPress installations but if any of your other plugins / general setup needs it you can enable it back again although it might cause other issues down the road.

    To enable it back you can do this:

    1] Log into your CPanel
    2] Search for "MultiPHP INI Editor" and open it up
    3] Select your website from the dropdown list to see the PHP options
    4] The last option should be the zlib.output_compression set to Disabled at the moment ( this was originaly enabled ).

    I hope this helps and gives closure to this issue!


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