Please help us help you and fill where relevant:
Your LimeSurvey version: Version 5.4.15+221212  (attempting to upgrade to LimeSurvey 5.6.0 build 230116)
Own server or LimeSurvey hosting: Own server
Survey theme/template: Custom
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We have upgraded our Limesurvey installation the past year with no problem by following the upgrade guide in the LS manual.

However after upgrading from LimeSurvey  Version 5.4.15+221212  to LimeSurvey 5.6.0 build 230116 we receive a 500 error:500: Internal server errorProperty "SurveyLanguageSetting.surveyls_alias is not defined.
I noticed another user received this error but no solution was posted yet.

Is this a DB error?


Thanks for your help,

Kind regards,

John


 

Looks like a bug in the updatescript. Sometimes is a bug happend earlier in the lifecycle of the installation.
From you description it's unclear if you no longer can login into LimeSurvey or if the issue is triggered when using existing surveys.

When you create a new survey, is the an issue?