Title: PHP error: Uncaught Error: Call to undefined function
Last modified: March 2, 2021

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# PHP error: Uncaught Error: Call to undefined function

 *  Resolved [tlcb](https://wordpress.org/support/users/tlcb/)
 * (@tlcb)
 * [5 years, 2 months ago](https://wordpress.org/support/topic/php-error-uncaught-error-call-to-undefined-function/)
 * Hello, I was using this plugin successfully with my previous WordPress site running
   on my own server: Nginx with PHP 5.6 (I think from memory) on Rasbian/Debian 
   Wheezy. I rebuilt the server with Rasberry OS/Debian Buster and PHP 7.4.
 * Wordpress is working fine apart from this plugin. I recreated the SSH user and
   keys and believe these are okay as I can login outside of PHP with them.
 * The NGINX log shows:
 *     ```
       2021/03/02 06:42:39 [error] 556#556: *15111 open() "/mnt/webfiles/websites/cabincontrol.tlcb.uk404.html" failed (2: No such file or directory), client: 10.5.248.122, server: cabincontrol.tlcb.uk, request: "GET /favicon.ico HTTP/1.1", host: "cabincontrol.tlcb.uk", referrer: "https://cabincontrol.tlcb.uk/heating.html"
       2021/03/02 08:36:49 [error] 556#556: *35635 FastCGI sent in stderr: "PHP message: PHP Fatal error:  Uncaught Error: Call to undefined function xml_parser_create() in /mnt/webfiles/websites/79th.tlcb.uk/wp-content/plugins/ssh-sftp-updater-support/phpseclib/Crypt/RSA.php:1468
       Stack trace:
       #0 /mnt/webfiles/websites/79th.tlcb.uk/wp-content/plugins/ssh-sftp-updater-support/phpseclib/Crypt/RSA.php(1785): Crypt_RSA->_parseKey()
       #1 /mnt/webfiles/websites/79th.tlcb.uk/wp-content/plugins/ssh-sftp-updater-support/class-wp-filesystem-ssh2.php(97): Crypt_RSA->loadKey()
       #2 /mnt/webfiles/websites/79th.tlcb.uk/wp-admin/includes/file.php(1861): WP_Filesystem_SSH2->connect()
       #3 /mnt/webfiles/websites/79th.tlcb.uk/wp-admin/includes/class-wp-upgrader.php(193): WP_Filesystem()
       #4 /mnt/webfiles/websites/79th.tlcb.uk/wp-admin/includes/class-plugin-upgrader.php(293): WP_Upgrader->fs_connect()
       #5 /mnt/webfiles/websites/79th.tlcb.uk/wp-admin/includes/ajax-actions.php(4452): Plugin_Upgrader->bulk_upgrade()
       #6 /mnt/webfiles/websites/79th.tlcb.uk/wp-includes/class-wp-hook.php(287): wp_ajax_upd" while reading response header from upstream, client: 10.5.248.124, server: 79th.tlcb.uk, request: "POST /wp-admin/admin-ajax.php HTTP/1.1", upstream: "fastcgi://unix:/var/run/php/php7.4-fpm.sock:", host: "79th.tlcb.uk", referrer: "https://79th.tlcb.uk/wp-admin/plugins.php"
       ```
   
 * I’m sure it’s a dependency I have not installed. I installed:
    php7.4-ssh2 and
   is at version: 1.2+0.13-9+0~20210223.17+debian10~1.gbp17d23d
 * and
    php-phpseclib which is at version: 2.0.14-1
 * What am I missing?
 * thanks

Viewing 2 replies - 1 through 2 (of 2 total)

 *  Plugin Author [David Anderson / Team Updraft](https://wordpress.org/support/users/davidanderson/)
 * (@davidanderson)
 * [5 years, 2 months ago](https://wordpress.org/support/topic/php-error-uncaught-error-call-to-undefined-function/#post-14138671)
 * Hi,
 * You need to activate the PHP module php-xml on your install.
 * David
 *  Thread Starter [tlcb](https://wordpress.org/support/users/tlcb/)
 * (@tlcb)
 * [5 years, 2 months ago](https://wordpress.org/support/topic/php-error-uncaught-error-call-to-undefined-function/#post-14140571)
 * Hi David
 * Brilliant, that worked. Initially I installed php-xml and it did not but then
   found out I needed to install php7.4-xml
 * Thanks for the help
 * David

Viewing 2 replies - 1 through 2 (of 2 total)

The topic ‘PHP error: Uncaught Error: Call to undefined function’ is closed to new
replies.

 * ![](https://s.w.org/plugins/geopattern-icon/ssh-sftp-updater-support.svg)
 * [SSH SFTP Updater Support](https://wordpress.org/plugins/ssh-sftp-updater-support/)
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 * [Unresolved Topics](https://wordpress.org/support/plugin/ssh-sftp-updater-support/unresolved/)
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 * 2 replies
 * 2 participants
 * Last reply from: [tlcb](https://wordpress.org/support/users/tlcb/)
 * Last activity: [5 years, 2 months ago](https://wordpress.org/support/topic/php-error-uncaught-error-call-to-undefined-function/#post-14140571)
 * Status: resolved