Purchase of used laptop no Windows key

My daughter recently purchased a slightly used (returned) laptop from Best Buy, but when she got it home, it didn’t have the key for Windows. She took it back and asked about the key and the dude fumbled around and searched the box, etc. Finally he just put a key into the machine to activate Windows, but he didn’t share the key with my daughter. I suspect he just put a corporate key from Best Buy into the machine, which I don’t think he’s supposed to do, but whatever. It feels weird that we don’t have the key. The Best Buy guy said we should have the key. It’s like $100 for a key (I think), which is close to the amount of the discount for purchasing a returned laptop (as opposed to getting new).

Now I am trying to decide if this is a good deal or not. How important is it to have the Windows activation key?

Assuming it’s Windows 10, once it activates, MS considers the motherboard hardware licensed. Reinstalling on the laptop down the road, without a key should still activate if needed.

Really? Oh, that’s a relief. Thanks so much! I was ready to go down there and roll my sleeves up. I can just be chill.

If you are concerned about not having the number, there are free apps to locate keys on your machine and print them for you.

You may want to check the activation status to be certain. Check this article:


Windows should automatically activate with pretty much any consumer laptop, as the key is embedded in the UEFI. You don’t get an actual key specific to your install. If it didn’t activate on its own, the laptop may be some sort of grey-market Chinese hardware or something.

Dumb question, but did you or her flip over the laptop and look for the windows key sticker that is usually affixed to the bottom?

i.e. image

Failing that, to get the key he typed in, which was probably some corporate best buy key they use, you can use this vbs script (save to the PC in question as a vbs file and double click to run)


Code from link for reference
Option Explicit
Dim objshell,path,DigitalID, Result
Set objshell = CreateObject("WScript.Shell")
'Set registry key path
Path = "HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\"
'Registry key value
DigitalID = objshell.RegRead(Path & "DigitalProductId")
Dim ProductName,ProductID,ProductKey,ProductData
'Get ProductName, ProductID, ProductKey
ProductName = "Product Name: " & objshell.RegRead(Path & "ProductName")
ProductID = "Product ID: " & objshell.RegRead(Path & "ProductID")
ProductKey = "Installed Key: " & ConvertToKey(DigitalID)
ProductData = ProductName & vbNewLine & ProductID & vbNewLine & ProductKey
'Show messbox if save to a file
If vbYes = MsgBox(ProductData & vblf & vblf & "Save to a file?", vbYesNo + vbQuestion, "BackUp Windows Key Information") then
Save ProductData
End If
'Convert binary to chars
Function ConvertToKey(Key)
Const KeyOffset = 52
Dim isWin8, Maps, i, j, Current, KeyOutput, Last, keypart1, insert
'Check if OS is Windows 8
isWin8 = (Key(66) \ 6) And 1
Key(66) = (Key(66) And &HF7) Or ((isWin8 And 2) * 4)
i = 24
Current= 0
j = 14
Current = Current* 256
Current = Key(j + KeyOffset) + Current
Key(j + KeyOffset) = (Current \ 24)
Current=Current Mod 24
j = j -1
Loop While j >= 0
i = i -1
KeyOutput = Mid(Maps,Current+ 1, 1) & KeyOutput
Last = Current
Loop While i >= 0

If (isWin8 = 1) Then
keypart1 = Mid(KeyOutput, 2, Last)
insert = "N"
KeyOutput = Replace(KeyOutput, keypart1, keypart1 & insert, 2, 1, 0)
If Last = 0 Then KeyOutput = insert & KeyOutput
End If
ConvertToKey = Mid(KeyOutput, 1, 5) & "-" & Mid(KeyOutput, 6, 5) & "-" & Mid(KeyOutput, 11, 5) & "-" & Mid(KeyOutput, 16, 5) & "-" & Mid(KeyOutput, 21, 5)
End Function
'Save data to a file
Function Save(Data)
Dim fso, fName, txt,objshell,UserName
Set objshell = CreateObject("wscript.shell")
'Get current user name
UserName = objshell.ExpandEnvironmentStrings("%UserName%")
'Create a text file on desktop
fName = "C:\Users\" & UserName & "\Desktop\WindowsKeyInfo.txt"
Set fso = CreateObject("Scripting.FileSystemObject")
Set txt = fso.CreateTextFile(fName)
txt.Writeline Data
End Function

Again modern computers typically don’t have individual keys, they’re embedded in the UEFI and Windows activates transparently.

Of course if you buy from a boutique or build your own you’ll have a key, but if you buy a Dell or HP or whatever, not.

Weird. It was a Dell she got from Best Buy. I did not look under the thing (but I should have thought of that!), but apparently neither did the Best Buy guy. He looked through the box, then typed in something. It seemed like a weird experience. @stusser so you’re saying the activation prompt from Windows 10 should never have appeared? It should have just registered itself automatically. I didn’t go down Best Buy to get the key, but I was there when the prompt appeared. It was a modal prompt. You couldn’t do anything but enter the key.

Oh, nice. I’ll get that key when I go home, problem solved.

Right, that should not have happened.

That win10 keyfinder program will find the embedded Dell key in the UEFI, not a unique one for your install. It may find your digital license as well, which is unique but can’t be used as a standard Windows key.

There are Dells that come without a windows license. Usually Ubuntu is installed, or freedos.

Nope, those have the windows license embedded too. You install Windows, it activates. Dell doesn’t bother making separate a separate hardware revision for such poorly-selling SKUs.

Maybe, I haven’t tried installing Windows 10 Home, only Pro, and that definitely does not have the license embedded.

You need to choose to skip the license when installing, then when it reboots into windows you should be able to activate it.

Err, right. On an unmodified installer. I changed the installer USB to always ask which edition after a couple of mis-installs and I always select Pro.

I don’t know if they have separate UEFI embedded keys for home vs pro on every model, you may only be licensed for home.

It registers the laptop for pro after entering a legitimate license for good afterwards.

Well sure, a paid real license key will always work. Point was the dell should have a key embedded in the UEFI BIOS that enables a digital entitlement for windows to activate without paying anything.

I’m not sure if that’s true for the freedos models. I’ll have to check it next week just to satisfy my curiosity.