WordPress update hangs after “Unpacking the update”

Monday, March 11th, 2019

If your WordPress installation updates just stops after showing the message “Unpacking the update”, try increasing the memory limit of PHP. Unzipping the update takes quite a bit of memory. Newer versions of WordPress keep getting larger and larger, requiring more memory to unpack. So it can suddenly break, as it did for me.

You may want to check the actual limit PHP is using by creating a small “php info” PHP page in your webroot and opening that in your browser. For example:

<?php
phpinfo();
?>

Name it something like “phpinfo_52349602384.php”. The random name is so that if you forget to remove the file, automated vulnerability scanners won’t find it. Open that file in the browser and the memory limit should be mentioned somewhere under “memory_limit”.