Editions, licensing and activation

Everything here only reads information; nothing changes your laptop’s licence. Use a normal PowerShell window unless a step says administrator. The same commands work on Windows Server, and you’ll use them on your lab servers right after installing them in Lesson 5.

1Read your licence with slmgr

slmgr is the Software Licensing Manager script that ships with Windows. Normally it shows its answers in pop-up boxes; running it through cscript prints them in the console instead, which is easier to read and copy.

Run these one at a time:

cscript //nologo C:\Windows\System32\slmgr.vbs /dli
cscript //nologo C:\Windows\System32\slmgr.vbs /xpr

You should see something like this:

Name: Windows(R), Professional edition
Description: Windows(R) Operating System, OEM_DM channel
Partial Product Key: 3V66T
License Status: Licensed

Windows(R), Professional edition:
    The machine is permanently activated.

/dli shows the edition, the channel (how the licence was sold) and the last five characters of the key. /xpr shows when activation expires. On an evaluation server you’ll see the channel include “EVAL” and an expiry date instead of “permanently activated”.

✅ Checkpoint: You can see your edition, licence channel and licence status.

2Read the same thing with PowerShell

Run this:

Get-CimInstance SoftwareLicensingProduct -Filter "Name LIKE 'Windows%' AND PartialProductKey IS NOT NULL" |
    Select-Object Name, ProductKeyChannel, LicenseStatus, GracePeriodRemaining

You should see something like this:

Name                             ProductKeyChannel LicenseStatus GracePeriodRemaining
----                             ----------------- ------------- --------------------
Windows(R), Professional edition OEM:DM                        1                    0

LicenseStatus 1 means licensed.

GracePeriodRemaining is in minutes; it’s 0 when activation never expires. On an evaluation or KMS-activated server it counts down, and dividing by 1440 gives days. That’s the line you’ll put in a monitoring script, because it works the same on every server.

✅ Checkpoint: LicenseStatus is 1 on your laptop, and you know how to turn GracePeriodRemaining into days.

3See which editions this Windows can become

In an administrator PowerShell window, run these one at a time:

DISM /Online /Get-CurrentEdition
DISM /Online /Get-TargetEditions

You should see something like this (your list may be different):

Deployment Image Servicing and Management tool
Version: 10.0.26100.5074

Image Version: 10.0.26100.6899

Current edition is:

Current Edition : Professional

The operation completed successfully.

Deployment Image Servicing and Management tool
Version: 10.0.26100.5074

Image Version: 10.0.26100.6899

Editions that can be upgraded to:

Target Edition : Education
Target Edition : Enterprise
Target Edition : ProfessionalEducation
Target Edition : ProfessionalWorkstation

The operation completed successfully.

These two commands only read.

On an evaluation server, the current edition is something like ServerDatacenterEval and the target list shows ServerDatacenter. You’d then convert with DISM /online /Set-Edition:ServerDatacenter /ProductKey:<your key> /AcceptEula. Don’t run Set-Edition on your laptop.

✅ Checkpoint: You can see your current edition and the editions it could be converted to.

4Build a core licence calculator

Paste this whole block into a normal PowerShell window:

function Get-CoreLicense {
    param(
        [int]$Processors,
        [int]$CoresPerProcessor,
        [int]$VMs,
        [ValidateSet('Standard', 'Datacenter')][string]$Edition
    )
    $perProcessor = [math]::Max(8, $CoresPerProcessor)            # at least 8 per processor
    $perServer    = [math]::Max(16, $Processors * $perProcessor)  # at least 16 per server
    if ($Edition -eq 'Datacenter') { $stacks = 1 }                 # unlimited VMs
    else { $stacks = [math]::Max(1, [math]::Ceiling($VMs / 2)) }  # 2 VMs per full set
    [pscustomobject]@{
        Edition       = $Edition
        VMs           = $VMs
        CoresPerStack = $perServer
        Stacks        = $stacks
        CoreLicenses  = $perServer * $stacks
        TwoCorePacks  = $perServer * $stacks / 2
    }
}

Now compare both editions for a host with two 12-core processors:

2, 6, 14 | ForEach-Object {
    Get-CoreLicense -Processors 2 -CoresPerProcessor 12 -VMs $_ -Edition Standard
    Get-CoreLicense -Processors 2 -CoresPerProcessor 12 -VMs $_ -Edition Datacenter
} | Format-Table

You should see this:

Edition    VMs CoresPerStack Stacks CoreLicenses TwoCorePacks
-------    --- ------------- ------ ------------ ------------
Standard     2            24      1           24           12
Datacenter   2            24      1           24           12
Standard     6            24      3           72           36
Datacenter   6            24      1           24           12
Standard    14            24      7          168           84
Datacenter  14            24      1           24           12

With 2 VMs both editions need the same 24 core licences, and Standard is much cheaper per licence, so Standard wins. With 14 VMs, Standard needs seven sets (168 core licences) while Datacenter still needs 24, so Datacenter wins. Put your company’s prices next to these numbers and the choice is easy.

✅ Checkpoint: Your table matches the one above, and you can explain why Standard needs 7 sets for 14 VMs.