Getting error 0xC004F074 when activating against KMS server


This error code is a very generic output to a KMS client having problems activating. To view your output, run slmgr.vbs –ato

When troubleshooting this problem, we checked the following details – if any were a problem, they would generate this error code:

  • DNS record not published at _VLMCS._tcp.client.domain. This must be an SRV record, which the KMS server will automatically register. If you have disabled this, you will need to use a GPO on the clients to point them to the correct KMS server to use
  • No network connectivity from the KMS client to the MS server on the KMS port (tcp/1688 by default). Install telnet on the client and run telnet KMS.Server.Name 1688 and make sure the screen goes blank
  • Not more than 4 hours time difference between KMS server and client. Check that your time zones are correct. If using server core, run timedate.cpl
  • No major hardware changes to the KMS server. If the KMS server is a VM and you have added a number of new devices, CPUs, memory etc, or P2Ved you will need to reactivate your KMS license
  • The KMS service must have the keys to issue for the KMS client requesting a license. For example, if the KMS server is Windows Server 2008 and you are trying to activate Windows 7, you will need an update installed on the KMS server AND the correct KMS key for Windows 7.

And the last one was the problem we hit: Our KMS server was Windows Server 2008 R2, just as the KMS clients. We’d crossed the threshold of 5 servers. But they still would not activate. The problem was that there are different license “channels” for Windows Server. They are described here:

Our servers which were having problems activating were all Windows Server 2008 R2 Datacenter Edition, and we had a “B Channel” KMS license installed on the KMS server.

We followed these steps on the KMS server to install the correct channel license:

  1. slmgr -upk
  2. slmgr -cpky
  3. slmgr -ipk <KMS Host Product Key - channel C>
  4. slmgr -ato

After doing the above, we ran slmgr -ato on the Windows Server 2008 R2 Datacenter Edition servers. Note that “Channel C” is able to active all lower level channels.

Comments (64)
  1. @Jeff: An example for Step 3 would be: slmgr /ipk ABC123-DEF456-GHI789-JKL012-MNO345

  2. @vikky : can you paste the entire text of your command prompt window here so I can see where the error is. Thanks.

    1. JACK says:

      In step 3
      syntax incorrect

  3. @Even: I’m not 100% sure what you are asking. But to sync a clock you run this command: w32tm /resync [/computer:] /nowait
    Where the /computername field is optional and means the computer whose clock should be synchronised using the existing settings defined on that computer. If you leave out this field, it means to sync the clock of the local machine. Domain joined machines automatically
    sync their clocks using the AD domain hierarchy to discover the closest DC.

  4. @Brendan. Sorry, you’d need to get support through your normal channel as this needs troubleshooting beyond what a blog comments section can provide.

  5. @Albert: Blog comments aren’t the forum for troubleshooting production issues. You should contact your TAM or SDM representing your Premier Support contract for assistance, or log a request for support here:

  6. @Jim: Not sure what you mean. It sounds like you ran these commands on a retail version of Windows? This instruction was clearly intended for the KMS server.

  7. @Tatenda: Windows 8 Pro can be installed in one of 2 ways: Retail or Volume License. Retail means OEM or via a box you buy from a shop. This is not compatible with KMS. You need to install Windows 8 Pro using Volume Licensing ISO file you download from your Volume Licensing website subscription. This will come with a well-know key in to instructing it to look for a KMS server. You can see these keys here:
    You can also use your MAK keys from your VL website subscription to active these.
    The only supported way to go from a Retail version to a VL version is to reinstall Windows.

  8. @Jomari – Sorry, you’d need to get support through your normal channel as this needs troubleshooting beyond what a blog comments section can provide.

  9. @Stilfari – Blog comments aren’t the forum for troubleshooting production issues. You should contact your TAM or SDM representing your Premier Support contract for assistance, or log a request for support here:
    To get you started however, I think the commands in the blog should re-activate your KMS key. If you tried them without success, then just build a new KMS computer and activate that. A single KMS key should be able to be activated not more than 5 times. KMS
    servers don’t retain any permanent "state" for activations.

  10. @jim: you need to enter the producy key after -ipk
    So, if your individual C-channel KMS Host Key is 11111-22222-33333-44444-55555, then the command is:
    slmgr -ipk 11111-22222-33333-44444-55555

  11. @Jess:
    Logon with the Microsoft Account (formerly Live ID) with rights to your volume license agreement.

  12. @Logavarthanan – The -ato switch means "Active Online". What this tells your KMS server to do it go to the Microsoft servers on the internet and consume one of your 5 KMS server activations. It sounds like your KMS server cannot get direct access to the
    internet. Use the command SLUI 4 to show you phone numbers you can dial to complete your KMS server activation. See here:

  13. Fabio Araujo says:

    Thank you for your information!!!


    I could solve a issue using your information!!!!

    Fabio, Brazil.

  14. vikky says:

    Hai i got syntax error

  15. Mark says:

    nice.. worked for me too

  16. David says:

    How do you open the command for KMS server? Is it in Command Prompt?

    More detailed steps for amateur users please

  17. @David: The command slmgr is a vbs script located at C:windowssystem32

    You can simply run the commands above, or if you'd like the output to the screen (instead of pop-ups), then open a command prompt (as administrator if needed) and change to c:windowssystem32 then run:

    cscript.exe slmgr.vbs with the switches stated above.

  18. Brendan says:

    Hi David,

    I’m having the same issue with Windows 8, and I was wondering if you could help me in any way at all? I have tried every available solution online, such as putting my Product Key through slmgr.vbs /ipk and Slui 3 and resetting the KMS timezone and fixing corrupted files on my computer, but to no avail.

    Any help would be appreciated, I’m all out of options.

    Thank you!

  19. Brendan says:

    Hi Craig* I mean, I’m really sorry, I read the wrong name!

  20. Tatenda says:

    hie Craig how do activate my windows 8 pro using slmgr.vbs/ato to activate and update KMS client information

  21. jim says:

    thanks a lot . . . it wiped my cd key and i don’t even have that anymore

  22. &even says:

    what helped for me was the clock issue.
    in case the machine is in workgroup there’s no sync to NTP server, so syncing the clock helped.
    any recommendation how to sync machines which are part of groups with the clock?

  23. Jomari says:

    does not work for me 🙁 it still not activated. please help

  24. Stilfari says:

    I was wondering if there was a way around having to reactivate the KMS server license.
    We had the KMS server running on a desktop with VMWare workstation while waiting for the server to arrive.

    We have received the server and installed ESXi on it, and exported the VM to .ovf and reimported it on the ESXi.
    The imported VM is not activated, and we cannot use the KMS server.

    Can you tell me what I can do?

    Thanks in advance.

  25. Max S. says:

    I’d love to give an input, I was reading your post and I think you might have just helped me: I went into my service(s) and I (ran) KMS, After that I went into the (CMD) and did the slmgr /ipk (xxxxxxxxxxxxxxxx) then slmgr/ -ato and won… (x It activated,
    after trying every method in the world, this worked. Thanks Craig!

  26. Jeff25 says:

    Hi Craig, like Vikki I’m getting a syntax error on step 3. Can you post an example? Thanks, Jeff

  27. Albert Krassy says:

    Hi, Could you help me on my sending email is not working properly, give me information how to fix this problem.


  28. jim says:

    Hai i got syntax error
    slmgr -ipk

  29. Jess says:

    I Craig, thanks for the info. so where do I find the KMS host key?

  30. Logavarthanan says:

    Sir, I have a the same error at the end of the last command. no key management service could be contacted

  31. vinod sharma says:


  32. hi guy says:

    it says that i need ‘elevated permision’ help!!!!

  33. @hi guy: That means that you need to right-click cmd and choose "Run as Administrator". Though, if you aren’t familiar with running elevated, then it’s probably best that you have someone from Microsoft Support guide you here as you could be in a different
    situation that the one that has been blogged about. Visit to get assistance.

  34. devesh says:

    Hi Craig
    I am having Windows 8 on my laptop and getting Error 0xC004F074 bla bla bla. No Key Management Services (KMS) could be contacted.

    Kindly suggest how to resolve the above issue in Windows 8

  35. @Devesh: Blog forums aren’t a good place to gather detailed information and start troubleshooting. Visit to get assistance with your specific problem.

  36. ivan says:

    i got to 1 and 2, it cleared my key then i entered 3 and i got a syntax error…

  37. @ivan: A syntax error means you made a typo. The format is slmgr -ipk 11111-22222-33333-44444-55555
    Be sure not to use copy and paste as the – sign has 2 meanings and some text display systems use the wrong dash.

  38. ivan says:

    i got to 1 and 2, it cleared my key then i entered 3 and i got a syntax error…

  39. ivan says:

    when you get to "slmgr -ipk ", what do you put as the host product key?

  40. @ivan: You enter your product key you retrieved from the volume license website:
    You need to login with an account that is authorised to access the site.

  41. ivan says:

    i dont know how to access that site. its asking for License numbers and authorization number and i have no idea how to get those. all i need is the product key to get my windows to work.

  42. @ivan: This blog post is specifically about activating Windows Server 2008 R2 Datacenter Edition against your own KMS server you run in your corporate environment. It sounds like you are having difficulties with a private copy of Windows client. If this
    is the case, please visit and follow the guides there to locate the right support option for you.

  43. Adrian says:

    why im still error?

  44. Adrian says:

    im at CLIENT VL

  45. @adrian: You’ll be best working with our paid per-incident support at

  46. Francis says:

    Francis from Ghana, having the same problem with my windows 10

  47. @Francis: See here for the steps needed to prepare your existing KMS server to activate your Windows 10 clients:
    Note that there is a special key on your volume license site for activating Windows 10 clients while Windows Server 2016 is not yet available. If your question relates to a single Windows 10 client having activation issues, then get support at

  48. Daniel says:

    Thanks, I was going nuts, and it was just a time of day mismatch issue!

  49. @Daniel: Good to hear it helped you.

  50. kayla says:

    Simply changing the port int he settings menu to 1690 did it for me

  51. D.Conmboni says:

    Thank you. It works.

  52. Kim Ewen says:

    We are having this issue for the first time in our corporate environment, and just noticed all these comments today, is there a wider issue?

    1. @Kim Ewen: You’ll be best working with our paid per-incident support at

  53. Cesar Tayapad says:

    Hi Craig,

    Is there a way to get kms licensing to work where kms host is on a different date/time than the kms client? Kms client server has more than 4hrs time difference.

    Thanks in advance.



    1. @Cesar Tayapad – Sorry it’s been so long since you posted. They can be in different time ZONES, but their UTC times need to be close. If they both have accurate time for the timezone they are set to, then your issue is something else. Make sure they have the correct time zones set and that their clocks are accurate for that time zone.

  54. Daniela says:

    Hi, I am a small youtuber and whenever I record on my handycam i get the memory card out of the camera and put on my windows 10 to view it and edit but when i want to watch the video it just says ” plateform not suppoted error 0xc04f074 or something like that please help

    1. @Daniela – Sorry that doesn’t have anything to do with a KMS server so isn’t relevant here. If you’d like help with your issue, if a Windows media player is used, then contact support at
      If you are using another media player to play the video (like VLC, then you’d need to contact the vendor of that program for help.

  55. Eddie says:

    We use Windows 7 exclusively for our end users and some time ago I updated our Server 2008 R2 to support Windows 8 and Windows 8.1 with the patches to support KMS activation from a request from our software developers. I ran into this error and double-checked everything and still a “no go” with this error. After some pain and suffering I installed KMS on our new Server 2012 R2 system that is going to replace the Server 2008 R2 system and everything just works. I sure wish the developers at Microsoft would share more insights into EVERY error code KMS throws as it is nearly impossible to troubleshoot and error where the client says it cannot contact the KMS server, but the KMS server shows it is receiving a request and not activating.

    1. @Eddie – If you have support questions, please do contact to get quick resolutions to issues.

  56. Mustafa says:

    1. Open an elevated command prompt.

    2. Enter the commands below one at a time, and press Enter after each command.

    cscript c:\windows\system32\slmgr.vbs /ipk XXXXX-XXXXX-XXXXX-XXXXX-XXXXX

    cscript c:\windows\system32\slmgr.vbs /ckms

    cscript c:\windows\system32\slmgr.vbs /skms KMS Host Name:1688

    cscript c:\windows\system32\slmgr.vbs /ato

  57. Saher says:

    I am unable to activate my windows 8 pro I tried out every possible solution
    Error Details Error code: 0xC004C003
    can you help me in fixing this issue

    1. @Saher – You’ll need to engage with our support team via to troubleshoot your problem

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