A product key looks like this: ABCDEF-123456-GHIJKL-789012-MNOPQR (5 times 6 characters).
Esko has many products that require multiple product keys, therefore, they are bundled in HTML files (product key files). A product key file looks like this:
Your product keys or product key files are sent to you via e-mail by Esko Support or by your Esko Sales Operations Agent. They are typically saved in a zip-file. Please also check your Spam or Junk Mailbox, it might be that the e-mail ended up there.