Hi Trevor,
thank you for your answer. Unluckily I cannot run custom scripts on remote machines, since I am authorized only to make small changes in their configuration (I managed to classify the definition of event filters and consumers as small modifications). To install a custom script, I should assure the compliance with the company software validation process, but this is out of scope for my project.
I will use the "sourcename" as identifier in the event log, until the insertionstringtemplate works.
Best regards,
Marzio