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 IaaS engineer in Sydney, Australia who refers to himself in the third person in bios. Wait, not BIOS… my brain should be EFI by now.

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

You can leave me a comment by contacting me, and I might publish your thoughts. Please read the FAQs first though.

If you found this post helpful or entertaining, you can shout me a coffee or buy some silly merch. Thanks!