Thread:Project:Support desk/Content not displayed

Hello, Mediawiki worked well for some time, but about a month ago, all content disappeared from the pages. By content I mean the text of the various articles. The articles are not visible, but if we check the source code, the text is still there. The wiki is hosted by a web hosting company.

Here is the content from php-erros.log, after we try to load the wiki:

[22-Jul-2015 17:27:43 Europe/Paris] PHP Warning: preg_match: Compilation failed: group name must start with a non-digit at offset 8 in /homepages/6/d387101406/htdocs/web/wikizodiac/includes/MagicWord.php on line 872

[22-Jul-2015 17:27:43 Europe/Paris] PHP Warning: preg_match_all: Compilation failed: group name must start with a non-digit at offset 4 in /homepages/6/d387101406/htdocs/web/wikizodiac/includes/MagicWord.php on line 846

[22-Jul-2015 17:27:43 Europe/Paris] PHP Warning: Invalid argument supplied for foreach in /homepages/6/d387101406/htdocs/web/wikizodiac/includes/MagicWord.php on line 847

[22-Jul-2015 17:27:43 Europe/Paris] PHP Warning: preg_replace: Compilation failed: group name must start with a non-digit at offset 4 in /homepages/6/d387101406/htdocs/web/wikizodiac/includes/MagicWord.php on line 851

[22-Jul-2015 17:27:43 Europe/Paris] PHP Warning: preg_match_all: Compilation failed: group name must start with a non-digit at offset 4 in /homepages/6/d387101406/htdocs/web/wikizodiac/includes/MagicWord.php on line 846

[22-Jul-2015 17:27:43 Europe/Paris] PHP Warning: Invalid argument supplied for foreach in /homepages/6/d387101406/htdocs/web/wikizodiac/includes/MagicWord.php on line 847

[22-Jul-2015 17:27:43 Europe/Paris] PHP Warning: preg_replace: Compilation failed: group name must start with a non-digit at offset 4 in /homepages/6/d387101406/htdocs/web/wikizodiac/includes/MagicWord.php on line 851

[22-Jul-2015 17:27:43 Europe/Paris] PHP Warning: preg_match: Compilation failed: group name must start with a non-digit at offset 8 in /homepages/6/d387101406/htdocs/web/wikizodiac/includes/MagicWord.php on line 872

[22-Jul-2015 17:27:43 Europe/Paris] PHP Warning: preg_match: Compilation failed: group name must start with a non-digit at offset 8 in /homepages/6/d387101406/htdocs/web/wikizodiac/includes/MagicWord.php on line 872

[22-Jul-2015 17:27:43 Europe/Paris] PHP Warning: preg_match_all: Compilation failed: group name must start with a non-digit at offset 4 in /homepages/6/d387101406/htdocs/web/wikizodiac/includes/MagicWord.php on line 846

[22-Jul-2015 17:27:43 Europe/Paris] PHP Warning: Invalid argument supplied for foreach in /homepages/6/d387101406/htdocs/web/wikizodiac/includes/MagicWord.php on line 847

[22-Jul-2015 17:27:43 Europe/Paris] PHP Warning: preg_replace: Compilation failed: group name must start with a non-digit at offset 4 in /homepages/6/d387101406/htdocs/web/wikizodiac/includes/MagicWord.php on line 851

[22-Jul-2015 17:27:43 Europe/Paris] PHP Warning: preg_match_all: Compilation failed: group name must start with a non-digit at offset 4 in /homepages/6/d387101406/htdocs/web/wikizodiac/includes/MagicWord.php on line 846

[22-Jul-2015 17:27:43 Europe/Paris] PHP Warning: Invalid argument supplied for foreach in /homepages/6/d387101406/htdocs/web/wikizodiac/includes/MagicWord.php on line 847

[22-Jul-2015 17:27:43 Europe/Paris] PHP Warning: preg_replace: Compilation failed: group name must start with a non-digit at offset 4 in /homepages/6/d387101406/htdocs/web/wikizodiac/includes/MagicWord.php on line 851

[22-Jul-2015 17:27:43 Europe/Paris] PHP Warning: preg_match: Compilation failed: group name must start with a non-digit at offset 8 in /homepages/6/d387101406/htdocs/web/wikizodiac/includes/MagicWord.php on line 872

[22-Jul-2015 17:27:43 Europe/Paris] PHP Warning: preg_match: Compilation failed: group name must start with a non-digit at offset 8 in /homepages/6/d387101406/htdocs/web/wikizodiac/includes/MagicWord.php on line 872

[22-Jul-2015 17:27:43 Europe/Paris] PHP Warning: preg_match: Compilation failed: group name must start with a non-digit at offset 8 in /homepages/6/d387101406/htdocs/web/wikizodiac/includes/MagicWord.php on line 872

[22-Jul-2015 17:27:43 Europe/Paris] PHP Warning: preg_match: Compilation failed: group name must start with a non-digit at offset 8 in /homepages/6/d387101406/htdocs/web/wikizodiac/includes/MagicWord.php on line 872

[22-Jul-2015 17:27:43 Europe/Paris] PHP Warning: preg_match: Compilation failed: group name must start with a non-digit at offset 8 in /homepages/6/d387101406/htdocs/web/wikizodiac/includes/MagicWord.php on line 872

[22-Jul-2015 17:27:43 Europe/Paris] PHP Warning: preg_match: Compilation failed: group name must start with a non-digit at offset 8 in /homepages/6/d387101406/htdocs/web/wikizodiac/includes/MagicWord.php on line 872

We use Mediawiki 1.19.0, Php 5.4, Mysql 5.1.73.

I welcome any suggestions to fix the problem.