My crystal ball is failing me so you'll have to provide some logs.

Presume the apache logs similar to when we were talking yesterday

    @wrongecho Thanks for that and below is the output

    [Sat Sep 21 18:28:05.961571 2024] [php:error] [pid 996] [client 192.168.12.9:56212] PHP Fatal error: Uncaught Error: Call to undefined function mb_detect_encoding() in /var/www/itflow.##.com/functions.php:737\nStack trace:\n#0 /var/www/itflow.##.com/portal/login.php(34): sanitizeInput()\n#1 {main}\n thrown in /var/www/itflow.##.com/functions.php on line 737

    [Sat Sep 21 18:29:06.067552 2024] [php:error] [pid 1231] [client 192.168.12.9:34468] PHP Fatal error: Uncaught Error: Call to undefined function mb_detect_encoding() in /var/www/itflow.##.com/functions.php:737\nStack trace:\n#0 /var/www/itflow.##.com/login.php(28): sanitizeInput()\n#1 {main}\n thrown in /var/www/itflow.##.com/functions.php on line 737

    [Sat Sep 21 18:29:11.115863 2024] [php:error] [pid 994] [client 192.168.12.9:34484] PHP Fatal error: Uncaught Error: Call to undefined function mb_detect_encoding() in /var/www/itflow.##.com/functions.php:737\nStack trace:\n#0 /var/www/itflow.##.com/portal/login.php(34): sanitizeInput()\n#1 {main}\n thrown in /var/www/itflow.##.com/functions.php on line 737

    [Sat Sep 21 18:30:13.618786 2024] [php:error] [pid 993] [client 192.168.12.9:38396] PHP Fatal error: Uncaught Error: Call to undefined function mb_detect_encoding() in /var/www/itflow.##.com/functions.php:737\nStack trace:\n#0 /var/www/itflow.##.com/login.php(28): sanitizeInput()\n#1 {main}\n thrown in /var/www/itflow.##.com/functions.php on line 737

    [Sat Sep 21 18:30:16.284542 2024] [php:error] [pid 995] [client 192.168.12.9:38408] PHP Fatal error: Uncaught Error: Call to undefined function mb_detect_encoding() in /var/www/itflow.##.com/functions.php:737\nStack trace:\n#0 /var/www/itflow.##.com/portal/login.php(34): sanitizeInput()\n#1 {main}\n thrown in /var/www/itflow.##.com/functions.php on line 737

    [Sat Sep 21 18:31:18.865553 2024] [php:error] [pid 997] [client 192.168.12.9:50594] PHP Fatal error: Uncaught Error: Call to undefined function mb_detect_encoding() in /var/www/itflow.##.com/functions.php:737\nStack trace:\n#0 /var/www/itflow.##.com/login.php(28): sanitizeInput()\n#1 {main}\n thrown in /var/www/itflow.##.com/functions.php on line 737

    [Sat Sep 21 18:31:23.918539 2024] [php:error] [pid 996] [client 192.168.12.9:57346] PHP Fatal error: Uncaught Error: Call to undefined function mb_detect_encoding() in /var/www/itflow.##.com/functions.php:737\nStack trace:\n#0 /var/www/itflow.##.com/portal/login.php(34): sanitizeInput()\n#1 {main}\n thrown in /var/www/itflow.##.com/functions.php on line 737

    [Sat Sep 21 18:32:19.223977 2024] [php:error] [pid 1231] [client 192.168.12.9:56660] PHP Fatal error: Uncaught Error: Call to undefined function mb_detect_encoding() in /var/www/itflow.##.com/functions.php:737\nStack trace:\n#0 /var/www/itflow.##.com/login.php(28): sanitizeInput()\n#1 {main}\n thrown in /var/www/itflow.##.com/functions.php on line 737

    [Sat Sep 21 18:32:24.034301 2024] [php:error] [pid 994] [client 192.168.12.9:43666] PHP Fatal error: Uncaught Error: Call to undefined function mb_detect_encoding() in /var/www/itflow.##.com/functions.php:737\nStack trace:\n#0 /var/www/itflow.##.com/portal/login.php(34): sanitizeInput()\n#1 {main}\n thrown in /var/www/itflow.##.com/functions.php on line 737

    [Sat Sep 21 18:32:56.519700 2024] [php:error] [pid 993] [client 192.168.4.103:64154] PHP Fatal error: Uncaught Error: Call to undefined function mb_detect_encoding() in /var/www/itflow.##.com/functions.php:737\nStack trace:\n#0 /var/www/itflow.##.com/check_login.php(36): sanitizeInput()\n#1 /var/www/itflow.##.com/inc_all_admin.php(7): require_once('...')\n#2 /var/www/itflow.##.com/admin_debug.php(2): require_once('...')\n#3 {main}\n thrown in /var/www/itflow.##.com/functions.php on line 737

    [Sat Sep 21 18:33:24.384175 2024] [php:error] [pid 997] [client 192.168.12.9:51404] PHP Fatal error: Uncaught Error: Call to undefined function mb_detect_encoding() in /var/www/itflow.##.com/functions.php:737\nStack trace:\n#0 /var/www/itflow.##.com/login.php(28): sanitizeInput()\n#1 {main}\n thrown in /var/www/itflow.##.com/functions.php on line 737

      Thanks, that was the fix. Interesting that my installation has been working up until today when the latest patches were pushed this afternoon. Did these updates require this extension?

      Fantastic.

      The update that required the extension was a result of our other post: https://forum.itflow.org/d/1106-cant-import-client-csv-file/

      I'll add the extension to the docs, but I don't think many others are likely to be effected because the extension was already installed on my Windows dev box, PR Review that runs Ubuntu and the demo that runs on Hestia (despite what the PHP docs say about it not being pre-installed).

      wrongecho changed the title to HTTP 500 Error Post Update - mb_detect_encoding - mbstring .
      wrongecho stickied the discussion .

      I got bit by this one. Debian 12 and no php-mbstring package installed. I could have sworn that I installed it when I upgraded from Debian 11.

      Weird…

      Maybe it should be added into the install script?

      install_packages() {
    apt-get update && apt-get -y upgrade
    apt-get install -y apache2 mariadb-server \
    php libapache2-mod-php php-intl php-mysqli php-gd \
    php-curl php-imap php-mailparse php-mbstring libapache2-mod-md \
    certbot python3-certbot-apache git sudo whois cron dnsutils

        The installation at my office was from a couple of years ago back when ITFlow still offered multi-company support.

        2 months later
        wrongecho unstickied the discussion .