I am trying to activate ESET software on an endpoint (client workstation)

ESET Support » Business & Enterprise (Server Product) Support » Installing/Uninstalling/Activating endpoint...

You might want to try this:

Our activation welcome package will walk you through to common questions, errors, problems about activation and licensing:

ESET product activation troubleshooting

ESET product activation glossary/resource list

Business FAQs about activation

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