I tried to upgrade my multi site installation of Wordpress to Pressbooks 4.0.0 but I’m getting an error which I’m not quite sure how to fix. Actually the autoload file of the composer as i can see, is included and it also exists.
I followed instructions on how to install the new update from here:
Any advice is appreciated.
Thank you!
Did you download the zip-File from the releases-page? It seems as if you just downloaded the git-files, but there some dependencies are missing.
Fatal error: Uncaught Error: Class ‘PressbooksMix\Assets’ not found in /var/www/vhosts/lvps84-39-103-248.mammuts-servidor.es/pressbooks.test-b.lvps84-39-103-248.mammuts-servidor.es/wp-content/themes/pressbooks-book/functions.php:32 Stack trace: #0 /var/www/vhosts/lvps84-39-103-248.mammuts-servidor.es/pressbooks.test-b.lvps84-39-103-248.mammuts-servidor.es/wp-includes/class-wp-hook.php(298): pressbooks_book_info_page(’’) #1 /var/www/vhosts/lvps84-39-103-248.mammuts-servidor.es/pressbooks.test-b.lvps84-39-103-248.mammuts-servidor.es/wp-includes/class-wp-hook.php(323): WP_Hook->apply_filters(NULL, Array) #2 /var/www/vhosts/lvps84-39-103-248.mammuts-servidor.es/pressbooks.test-b.lvps84-39-103-248.mammuts-servidor.es/wp-includes/plugin.php(453): WP_Hook->do_action(Array) #3 /var/www/vhosts/lvps84-39-103-248.mammuts-servidor.es/pressbooks.test-b.lvps84-39-103-248.mammuts-servidor.es/wp-includes/script-loader.php(1296): do_action(‘wp_enqueue_scri…’) #4 /var/www/vhosts/lvps84-39-103-248.mammuts-servidor.es/pressbooks.test-b.lvp in /var/www/vhosts/lvps84-39-103-248.mammuts-servidor.es/pressbooks.test-b.lvps84-39-103-248.mammuts-servidor.es/wp-content/themes/pressbooks-book/functions.php on line 32
Yes i downloaded everything from the releases 
Oh, I know what the issue is. Hang on.
Can you try again by downloading the new zip (pressbooks-book-1.9.0-RC3.zip) from here? https://github.com/pressbooks/pressbooks-book/releases/tag/1.9.0-RC3
Thank you so much Ned it Worked!!!
