on a client server - I add repository ppandrej and installed debsury php7.2. installed all extensions like mysql, gd, curl etc. after that I am not able to access ISPCONFIG Panel. in the error log I see Code: [Tue Feb 09 18:06:54.869095 2021] [fcgid:warn] [pid 15144] [client 49.37.5.140:56564] mod_fcgid: stderr: PHP Fatal error: Uncaught Error: Call to undefined function mb_detect_encoding() in /usr/local/ispconfig/interface/lib/classes/db_mysql.inc.php:527 [Tue Feb 09 18:06:54.869234 2021] [fcgid:warn] [pid 15144] [client 49.37.5.140:56564] mod_fcgid: stderr: Stack trace: [Tue Feb 09 18:06:54.869242 2021] [fcgid:warn] [pid 15144] [client 49.37.5.140:56564] mod_fcgid: stderr: #0 /usr/local/ispconfig/interface/lib/classes/db_mysql.inc.php(179): db->escape('interface') [Tue Feb 09 18:06:54.869260 2021] [fcgid:warn] [pid 15144] [client 49.37.5.140:56564] mod_fcgid: stderr: #1 /usr/local/ispconfig/interface/lib/classes/db_mysql.inc.php(298): db->_build_query_string('SELECT `value` ...', 'interface', 'session_timeout') [Tue Feb 09 18:06:54.869267 2021] [fcgid:warn] [pid 15144] [client 49.37.5.140:56564] mod_fcgid: stderr: #2 /usr/local/ispconfig/interface/lib/classes/db_mysql.inc.php(337): db->_query('SELECT `value` ...', 'interface', 'session_timeout') [Tue Feb 09 18:06:54.869272 2021] [fcgid:warn] [pid 15144] [client 49.37.5.140:56564] mod_fcgid: stderr: #3 /usr/local/ispconfig/interface/lib/classes/db_mysql.inc.php(363): db->query('SELECT `value` ...', 'interface', 'session_timeout') [Tue Feb 09 18:06:54.869278 2021] [fcgid:warn] [pid 15144] [client 49.37.5.140:56564] mod_fcgid: stderr: #4 /usr/local/ispconfig/interface/lib/app.inc.php(166): db->queryOneRecord('SELECT `value` ...', 'interface', 'session_timeout') [Tue Feb 09 18:06:54.869283 2021] [fcgid:warn] [pid 15144] [client 49.37.5.140:56564] mod_fcgid: stderr: #5 /usr/local/ispconfig/interface/lib/app.inc.php(93): app->conf('interface', 'session_timeout') [Tue Feb 09 18:06:54.869288 2021] [fcgid:warn] [pid 15144] [client 49.37.5.140:56564] mod_fcgid: stderr: #6 /usr/local/ispconfig/interface/lib/app.inc.php(398): app->initialize_session() [Tue Feb 09 18:06:54.869293 2021] [fcgid:warn] [pid 15144] [client 49.37.5.140:56564] mod_fcgid: stderr: #7 /usr/local/ispconfig/interface/web/index.php(32): require_once in /usr/local/ispconfig/interface/lib/classes/db_mysql.inc.php on line 527 How I can fix this? from the only website I installed I can access phpinfo file. which is showing as 7.0.33 and mbstring enabled.
You have installed a new PHP version without mbstring extension and that's causing the error. Take care to switch the system php back to the correct original version after installing a additional PHP version, see chapter 9 here for the commands: https://www.howtoforge.com/tutorial...fig-3-from-debian-packages-on-debian-8-and-9/