Thread:Project:Support desk/fatal error out of nowhere

We have (had) a functioning wiki at http://wiki.secteuretablissement.org , and suddenly we have a fatal error on all pages, as shown below.

Any thoughts on what the problem might be? It appeared suddenly, no changes were made to the install.

MediaWiki	1.16.2 PHP	5.3.19 (cgi-fcgi) MySQL	5.0.96-community-log

Many thanks for any input.

Paul N.

MagicWordArray::parseMatch: parameter not found Backtrace:
 * 1) 0 /home/atwork/public_html/atworkwiki/w/includes/MagicWord.php(723): MagicWordArray->parseMatch(Array)
 * 2) 1 /home/atwork/public_html/atworkwiki/w/includes/parser/Parser.php(2820): MagicWordArray->matchStartAndRemove('SITENAME')
 * 3) 2 /home/atwork/public_html/atworkwiki/w/includes/parser/Preprocessor_DOM.php(962): Parser->braceSubstitution(Array, Object(PPFrame_DOM))
 * 4) 3 /home/atwork/public_html/atworkwiki/w/includes/parser/Parser.php(2728): PPFrame_DOM->expand(Object(PPNode_DOM), 0)
 * 5) 4 /home/atwork/public_html/atworkwiki/w/includes/parser/Parser.php(513): Parser->replaceVariables('$1 - {{SITENAME...')
 * 6) 5 /home/atwork/public_html/atworkwiki/w/includes/parser/Parser.php(4189): Parser->preprocess('$1 - {{SITENAME...', Object(Title), Object(ParserOptions))
 * 7) 6 /home/atwork/public_html/atworkwiki/w/includes/MessageCache.php(673): Parser->transformMsg('$1 - {{SITENAME...', Object(ParserOptions))
 * 8) 7 /home/atwork/public_html/atworkwiki/w/includes/GlobalFunctions.php(744): MessageCache->transform('$1 - {{SITENAME...')
 * 9) 8 /home/atwork/public_html/atworkwiki/w/includes/GlobalFunctions.php(707): wfMsgGetKey('pagetitle', true, false, true)
 * 10) 9 /home/atwork/public_html/atworkwiki/w/includes/GlobalFunctions.php(613): wfMsgReal('pagetitle', Array, true)
 * 11) 10 /home/atwork/public_html/atworkwiki/w/includes/OutputPage.php(481): wfMsg('pagetitle', 'Main Page/fr')
 * 12) 11 /home/atwork/public_html/atworkwiki/w/includes/Article.php(785): OutputPage->setPageTitle('Main Page/fr')
 * 13) 12 /home/atwork/public_html/atworkwiki/w/includes/Wiki.php(493): Article->view
 * 14) 13 /home/atwork/public_html/atworkwiki/w/includes/Wiki.php(70): MediaWiki->performAction(Object(OutputPage), Object(Article), Object(Title), Object(User), Object(WebRequest))
 * 15) 14 /home/atwork/public_html/atworkwiki/w/index.php(117): MediaWiki->performRequestForTitle(Object(Title), Object(Article), Object(OutputPage), Object(User), Object(WebRequest))
 * 16) 15 {main}