Error Upgrade OJS 3.1.1.4 to 3.1.2 "You are trying to downgrade the product "" from version [3.1.1.4] to version [1.0.0.0]"

Dear @asmecher,

thank you for your reply!

I have removed the entries ‘openAIRE’ from the database and afterwards the update process of OJS 3.1.2.1 has been completed without receiving any error message. But unfortunately, the website remained faulty after the update. Many links don’t work and I can’t log into the backend.

Afterwards, I have tried a completely new installation of OJS 3.1.2.1 with a newly created database to avoid errors from the former installation. I imported our old database after the installation.

The result is this: On the website, the header is missing and the iframe is not loaded correctly. But the fonts look just fine, so the CSS seems to be included correctly.

Unfortunately, I still am not able to login properly. The login itself somehow does seem to work (see screenshot), but the backend is not loaded.
Unbenannt-1

Switching to English does not work either.

The following error message is always displayed at the top of the website:

Strict Standards : Declaration of DRIVERDAO::setOAI() should be compatible with PKPOAIDAO::setOAI($oai) in /home/suburban/public_html/sys_neu/plugins/generic/driver/DRIVERDAO.inc.php on line 19

Strict Standards : Declaration of CustomBlockPlugin::getBlockContext() should be compatible with BlockPlugin::getBlockContext($contextId = NULL) in /home/suburban/public_html/sys_neu/plugins/generic/customBlockManager/CustomBlockPlugin.inc.php on line 134

Strict Standards : Declaration of OpenAIREDAO::setOAI() should be compatible with PKPOAIDAO::setOAI($oai) in /home/suburban/public_html/sys_neu/plugins/generic/openAIRE/OpenAIREDAO.inc.php on line 100

Strict Standards : Only variables should be assigned by reference in /home/suburban/public_html/sys_neu/pages/index/IndexHandler.inc.php on line 68

Warning : Cannot modify header information - headers already sent by (output started at /home/suburban/public_html/sys_neu/plugins/generic/driver/DRIVERDAO.inc.php:19) in /home/suburban/public_html/sys_neu/lib/pkp/classes/template/PKPTemplateManager.inc.php on line 836

Warning : Cannot modify header information - headers already sent by (output started at /home/suburban/public_html/sys_neu/plugins/generic/driver/DRIVERDAO.inc.php:19) in /home/suburban/public_html/sys_neu/lib/pkp/classes/template/PKPTemplateManager.inc.php on line 837

Clicking on the “Issues” does not work and returns the following error:

Parse error : syntax error, unexpected ‘?’ in /home/suburban/public_html/sys_neu/lib/pkp/lib/vendor/illuminate/support/Str.php on line 681

Clicking on “Current” issue does not work either:

Deprecated : Non-static method PKPApplication::getCCLicenseBadge() should not be called statically, assuming $this from incompatible context in /home/suburban/public_html/sys_neu/pages/article/ArticleHandler.inc.php on line 162
Strict Standards : Declaration of SubmissionKeywordEntryDAO::getByControlledVocabId() should be compatible with ControlledVocabEntryDAO::getByControlledVocabId($controlledVocabId, $rangeInfo = NULL, $filter = NULL) in /home/suburban/public_html/sys_neu/lib/pkp/classes/submission/SubmissionKeywordEntryDAO.inc.php on line 20
Warning : assert(): Assertion failed in /home/suburban/public_html/sys_neu/lib/pkp/classes/identity/Identity.inc.php on line 157
Fatal error : Uncaught exception ‘Seboettg\CiteProc\Exception\CiteProcException’ with message ‘Illegal argument. Name has no family name.’ in /home/suburban/public_html/sys_neu/plugins/generic/citationStyleLanguage/lib/vendor/seboettg/citeproc-php/src/Seboettg/CiteProc/Util/NameHelper.php:120Stack trace: #0 /home/suburban/public_html/sys_neu/plugins/generic/citationStyleLanguage/lib/vendor/seboettg/citeproc-php/src/Seboettg/CiteProc/Rendering/Name/Name.php(528): Seboettg\CiteProc\Util\NameHelper::normalizeName(Object(stdClass)) #1 /home/suburban/public_html/sys_neu/plugins/generic/citationStyleLanguage/lib/vendor/seboettg/citeproc-php/src/Seboettg/CiteProc/Rendering/Name/Name.php(202): Seboettg\CiteProc\Rendering\Name\Name->nameOrder(Object(stdClass), 0) #2 /home/suburban/public_html/sys_neu/plugins/generic/citationStyleLanguage/lib/vendor/seboettg/citeproc-php/src/Seboettg/CiteProc/Rendering/Name/Name.php(184): Seboettg\CiteProc\Rendering\Name\Name->getNamesString(Object(stdClass), 0) #3 /home/suburban/public_html/sys_ne in /home/suburban/public_html/sys_neu/plugins/generic/citationStyleLanguage/lib/vendor/seboettg/citeproc-php/src/Seboettg/CiteProc/Util/NameHelper.php on line 120

Sometimes I also get the following error message

Fatal error: Uncaught → Smarty Compiler: Syntax error in template “app:app:frontendcomponentsheader.” on line 28 “{if !$pageTitleTranslated}{translate|assign:“pageTitleTranslated” key=$pageTitle}{/if}” unknown modifier ‘assign’ ← thrown in /home/suburban/public_html/sys_neu/lib/pkp/lib/vendor/smarty/smarty/libs/sysplugins/smarty_internal_templatecompilerbase.php on line 28

Could the bug have something to do with the migration from PHP version 5.6 to 7.1?

Or maybe with the QuickSubmit plugin? The user Hugo_Melo has had similar problems during his update

Sorry, I am really lost right now.

I am very grateful for any help or advice!