Thread:Project:Support desk/Fatal exception of type MWException after upgrade to MW from 1.19 to 1.20/reply (5)

I got Fatal exception of type MWException too just after I replaced MW 1.19 files by MW 1.20.2 files.

Here's backtrace:

Error: invalid magic word 'canonicalurl'

Backtrace:


 * 1) 0 /home/i/iu5201/mywiki/public_html/includes/MagicWord.php(236): MagicWord->load('canonicalurl')
 * 2) 1 /home/i/iu5201/mywiki/public_html/includes/parser/Parser.php(4765): MagicWord::get('canonicalurl')
 * 3) 2 /home/i/iu5201/mywiki/public_html/includes/parser/CoreParserFunctions.php(54): Parser->setFunctionHook('canonicalurl', Array, 1)
 * 4) 3 /home/i/iu5201/mywiki/public_html/includes/parser/Parser.php(253): CoreParserFunctions::register(Object(Parser))
 * 5) 4 [internal function]: Parser->firstCallInit
 * 6) 5 /home/i/iu5201/mywiki/public_html/includes/StubObject.php(79): call_user_func_array(Array, Array)
 * 7) 6 /home/i/iu5201/mywiki/public_html/includes/StubObject.php(99): StubObject->_call('firstCallInit', Array)
 * 8) 7 /home/i/iu5201/mywiki/public_html/includes/cache/MessageCache.php(829): StubObject->__call('firstCallInit', Array)
 * 9) 8 /home/i/iu5201/mywiki/public_html/includes/cache/MessageCache.php(829): StubObject->firstCallInit
 * 10) 9 /home/i/iu5201/mywiki/public_html/includes/cache/MessageCache.php(807): MessageCache->getParser
 * 11) 10 /home/i/iu5201/mywiki/public_html/includes/Message.php(618): MessageCache->transform('$1 ??? {{SITENA...', true, Object(LanguageRu), Object(Title))
 * 12) 11 /home/i/iu5201/mywiki/public_html/includes/Message.php(436): Message->transformText('$1 ??? {{SITENA...')
 * 13) 12 /home/i/iu5201/mywiki/public_html/includes/Message.php(476): Message->toString
 * 14) 13 /home/i/iu5201/mywiki/public_html/includes/OutputPage.php(790): Message->text
 * 15) 14 /home/i/iu5201/mywiki/public_html/includes/OutputPage.php(833): OutputPage->setHTMLTitle(Object(Message))
 * 16) 15 /home/i/iu5201/mywiki/public_html/includes/Article.php(485): OutputPage->setPageTitle('???????????????...')
 * 17) 16 /home/i/iu5201/mywiki/public_html/includes/actions/ViewAction.php(37): Article->view
 * 18) 17 /home/i/iu5201/mywiki/public_html/includes/Wiki.php(427): ViewAction->show
 * 19) 18 /home/i/iu5201/mywiki/public_html/includes/Wiki.php(304): MediaWiki->performAction(Object(Article))
 * 20) 19 /home/i/iu5201/mywiki/public_html/includes/Wiki.php(536): MediaWiki->performRequest
 * 21) 20 /home/i/iu5201/mywiki/public_html/includes/Wiki.php(446): MediaWiki->main
 * 22) 21 /home/i/iu5201/mywiki/public_html/index.php(59): MediaWiki->run
 * 23) 22 {main}

What should I do to fix this?