PCLZIP_ERR_BAD_FORMAT (-10) : Invalid archive structure


If WordPress spits out the above error message when installing plugins or themes, you might not have the required PHP curl installed, or a mismatched version.

Assuming you’re using PHP 7.4, you’ll want to install php74-curl or php-curl on FreeBSD, NetBSD/pkgsrc, or Debian-based Linux distros.

This a perfect case study in bad error messages. A layperson would see that error and assume an invalid archive means… an invalid archive. It’s technically correct, and entirely meaningless, to say a non-existent download would also be an invalid archive.

Author bio and support


Ruben Schade is a technical writer and infrastructure architect in Sydney, Australia who refers to himself in the third person. Hi!

The site is powered by Hugo, FreeBSD, and OpenZFS on OrionVM, everyone’s favourite bespoke cloud infrastructure provider.

If you found this post helpful or entertaining, you can shout me a coffee or send a comment. Thanks ☺️.