Core.Agent.CustomerSearch is undefined

[hitazcl]

I'm looking for the right solution to solve the "Core.Agent.CustomerSearch is undefined"-problem in the AgentTicketEmail-Action.
I've found a link of 2010, but I am not understanding the CVS language.
Is somebody here who'll let me know the final (whole) solution for that problem?
Thank you in advance.
Regards

Edited:
Okay, found something that sounds similar under this link.
I did it and the Action AgentTicketEmail is given again without an error!

But I have the problem if I want zoom a config item...
It is the action "AgentITSMConfigItemZoom"