World of EUC

use kms or adba. those will license the machines that mcs creates.

They use a key they get from the Microsoft Volume Licensing Service Center

Does this help?
<https://support.citrix.com/article/CTX128580/xendesktop-support-for-microsoft-kms-and-mak-activation-with-machine-creation-services|https://support.citrix.com/article/CTX128580/xendesktop-support-for-microsoft-kms-and-mak-activation-with-machine-creation-services>

Microsoft Volume Licensing Service Center has MAK and KMS. Like <@UL8ACTGSF> stated, if using KMS it will handle it.  Citrix does supported MAK based now, but it's in recent versions.
<https://docs.citrix.com/en-us/citrix-virtual-apps-desktops/install-configure/machine-catalogs-create.html#volume-licensing-activation>

The documentation is kind of confusing. I'm using MCS to create new VMs. I get that I have to install the key on the master image. Do I do on-line activation or offline?