Windows and Office Activation Glossary: HWID, GVLK, KMS, MAK, Ohook, TSforge

Plain-language definitions of the licensing terms that appear in activation guides and MAS documentation, with how each term relates to the others.

A glossary for activation terminology

Activation discussions mix Microsoft's official licensing vocabulary with community tool names. Confusing the two is the root of a surprising number of failed attempts. Here is each term, what it actually refers to, and who defines it.

Digital licence (digital entitlement)

A Microsoft-side record linking an activated Windows installation to a hardware fingerprint. Because the record lives on Microsoft's servers, reinstalling the same edition on the same hardware reactivates automatically. Defined by Microsoft.

HWID

Community shorthand for the hardware-bound digital licence path. In MAS, "HWID" is the menu entry that targets this mechanism for supported client editions. The term is a tool name; the underlying licence is Microsoft's.

KMS (Key Management Service)

Microsoft's volume activation service for organisations. Clients activate against a KMS host and renew on a fixed interval — historically 180 days. Defined by Microsoft.

GVLK (Generic Volume Licence Key)

Public keys Microsoft publishes so that a volume installation knows to look for a KMS host. They are not secret and they are not activation on their own.

MAK (Multiple Activation Key)

A volume key with a fixed number of activations that contacts Microsoft directly rather than a KMS host. Defined by Microsoft.

CSVLK

The host key an organisation installs on its KMS server so the server can service clients. Defined by Microsoft.

KMS38

A community method name. It targets the Windows client's KMS expiry so the activation runs far into the future instead of on the standard renewal cycle. Not a Microsoft term.

Online KMS

Community shorthand for activating against a KMS responder, with a scheduled renewal. Renewal-based rather than permanent.

Ohook

The Office-specific method documented by the upstream MAS project. Not a Microsoft term, and not related to KMS client keys.

TSforge

A newer method name in the same project, aimed at products the older methods do not cover. Behaviour differs by product; the upstream notes are the authority.

Notification mode

The state Windows enters when a grace period ends without activation: watermark, personalisation restrictions, periodic reminders. The system keeps working.

Grace period

The window in which a product functions while unactivated or awaiting renewal. Length varies by product and channel.

slmgr / ospp.vbs

Microsoft's own inspection tools for Windows and Office licensing respectively. Neither is part of any activation script; both are the correct way to verify results.

How the terms fit together

Microsoft defines the licensing mechanisms: digital licences, KMS, MAK, GVLK. Community tools such as MAS give names to procedures that use those mechanisms. When a guide says "use HWID", it is naming a procedure, not a Microsoft product feature. Keeping that distinction clear makes error messages far easier to interpret — an error that comes from the Software Licensing Service is a Microsoft error, regardless of which script triggered it.

For authoritative method behaviour, read the upstream project documentation rather than paraphrased guides.

massgrave.download is an independent documentation and troubleshooting resource. It is not the official Massgrave project. The official project lives at massgrave.dev and github.com/massgravel.