Hi @Felipe Jiménez,
Microsoft Q&A is an English forum, I translate your issuse like below.
I work for a company and we are setting up a new server. In the previous one we had a SQL Server Standard Edition 2017 license and we want to transfer that license to the new server. But we cannot find the email with the product activation key
For question regarding pricing / licensing please contact a Microsoft sales partner or licensing expert.
Call (1-800-426-9400), Monday through Friday, 6:00 AM to 6:00 PM PST to speak directly to Microsoft licensing specialist.
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