Recently I upgraded OTRS to latest from a previous OTRS 5.23. 

Everything seemed to go fine and easy, but now I am doing some tests and after I create a Ticket I get an Internal Server Error and the following message 

[Fri Jun 15 10:43:02.953674 2018] [:error] [pid 9867] Can't locate object method "ArticleContentIndex" via package "Kernel::System::Ticket" at /opt/otrs//Kernel/Modules/AgentTicketZoom.pm line 729.\n

Has anyone seen this before. 

I am running OTRS 6.0.8 on CentOS 7 with Mysql. 

Currently a test system with less than 100 tickets, I ran a Ticket Delete Process and reset Ticket Counter.log. 

I looked in another system with OTRS 5 and it does have a reference to that method into TIcket Modules. 

Regards 

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