How to fix Windows activation error 0x803FABB8?

Issue: Hi, I had some issues with my PC constantly crashing, so I decided to reinstall. While my crashes were now gone, I noticed that my Windows is no longer activated, and the message says there's an activation issue – error code 0x803FABB8. I am not sure how to go about this because I did use genuine Windows before, which I got as a free upgrade back with Windows 10 release. I have no clue what my key is or how to retrieve it. Any help would be appreciated.

Solved Answer

Microsoft has released many versions of its ever-improving operating system Windows, some of which were loved by users, while others having a relatively negative reception – Windows Vista is one of the best such examples. Technically, all the operating systems can still be run if the user really wants to, although it is highly advised against by the software developers.

Unsupported systems, such as Windows 7 or XP, might result in serious security issues, as they are unable to receive the most recent updates to patch software vulnerabilities. Besides, each of the new Windows versions brings in major bug fixes, new features, UI[1] iterations, and overall quality of life improvements across the board.

Therefore, the need for system upgrades is always something many users are keen on doing – a process that sometimes might be stopped by errors such as 0x803FABB8. While some errors stop the upgrade process completely, this particular error only shows up within the Activation section of the Settings panel and reads as follows:

We can't activate Windows on this device right now. You can try activating again later or go to the Store to buy genuine Windows. Error code: 0x803FABB8

The error message implies that the license for the operating system is not valid or that the Windows was installed illegally. However, the problem persists for those who do have a valid license and acquired it either by purchasing the OS or when they received it as a free upgrade for Windows 10.

How to fix Windows activation error 0x803FABB8?

The problem is that the digital license is not being correctly recognized, and the error 0x803FABB8 fix can be performed via several methods. Keep in mind that some of these solutions might not work for you. Likewise, if you are running an illegitimate version of the operating system, none of the methods will work.

OS activation issues became especially prominent when they tried to use a free upgrade back in 2015 when Windows 10 was released. In fact, we have previously discussed such problems in our articles for 0x8007267C, 0xC004F213, 0xC004F074, and many others.

With Windows 11 release,[2] many users were eager to try the new operating system (they need to meet certain system requirements) and seems that they encountered the same problem. Regardless of which operating system you are using, we recommend you first check it with a powerful PC repair tool FortectMac Washing Machine X9 to ensure that there are no underlying issues, such as malware[3] infection, that could be causing the error.

1. Run the troubleshooter

If you haven't done so already, you should run the troubleshooter for the error.

  • Right-click on Start and select Settings
  • Go to the Update & Security section
  • Select Activation on the left
  • Under the error code, click Troubleshoot Run the troubleshooter
  • Wait till the troubleshooter scans your computer and provides you with a solution.

At this point, many people receive the “Unable to activate Windows.” If that is the case, proceed with the solutions below.

2. Install all the updates for Windows

Fix it now! Fix it now!
To repair damaged system, you have to purchase the licensed version of Fortect Mac Washing Machine X9.

Inability to upgrade correctly could be caused by incorrectly installed or corrupted Windows updates. Applying all the latest updates could help you fix this issue:

  • Type Updates in Windows search and hit Enter
  • On the right side, click Check for updates
  • Wait till all the data is downloaded and installed, and don't forget to install all the optional updates
  • After it's done, reboot the computer Install all Windows updates
  • Try upgrading to the newest version again.

3. Activate via Command Prompt

If you are using a digital license, proceed with the following:

  • Type cmd in Windows search
  • Right-click on Command Prompt and select Run as administrator
  • When User Account Control shows up, click Yes
  • Once Command Prompt opens, copy and paste the following command:
    slmgr /xpr
  • Press Enter. Activate via Command Prompt

If you are using a product key, use the following instructions:

  • Open Command Prompt as administrator once again and use the following command:
    wmic path softwarelicensingservice get OA3xOriginalProductKey
  • Paste the slmgr.vbs.ipk <product key> into the window, and press Enter
  • Finally, use slmgr.vbs/ato command and hit Enter
  • Restart your PC and see if your Windows is activated.

4. Activate via phone

Fix it now! Fix it now!
To repair damaged system, you have to purchase the licensed version of Fortect Mac Washing Machine X9.

You can also activate Windows via your local phone line. Use this option if none of the above helped you.

  • Press Win + R and type Slui 4, press Enter
  • In the new window, select your country and press Next
  • This should provide you with a local support number
  • Pick up your phone and call it – follow the automated instructions. Activate via Phone

Note: you might need to provide some information about your Windows license. To acquire it, open Command Prompt as administrator and type in slmgr.vbs /dlv command and hit Enter – it should show you more details you might need while on the call.

Repair your Errors automatically team is trying to do its best to help users find the best solutions for eliminating their errors. If you don't want to struggle with manual repair techniques, please use the automatic software. All recommended products have been tested and approved by our professionals. Tools that you can use to fix your error are listed bellow:

do it now!
Download Fix
do it now!
Download Fix
Compatible with Microsoft Windows Compatible with OS X
Still having problems?
If you failed to fix your error using FortectMac Washing Machine X9, reach our support team for help. Please, let us know all details that you think we should know about your problem.
Fortect - a patented specialized Windows repair program. It will diagnose your damaged PC. It will scan all System Files, DLLs and Registry Keys that have been damaged by security threats.Mac Washing Machine X9 - a patented specialized Mac OS X repair program. It will diagnose your damaged computer. It will scan all System Files and Registry Keys that have been damaged by security threats.
This patented repair process uses a database of 25 million components that can replace any damaged or missing file on user's computer.
To repair damaged system, you have to purchase the licensed version of Fortect malware removal tool.To repair damaged system, you have to purchase the licensed version of Mac Washing Machine X9 malware removal tool.

Prevent websites, ISP, and other parties from tracking you

To stay completely anonymous and prevent the ISP and the government from spying on you, you should employ Private Internet Access VPN. It will allow you to connect to the internet while being completely anonymous by encrypting all information, prevent trackers, ads, as well as malicious content. Most importantly, you will stop the illegal surveillance activities that NSA and other governmental institutions are performing behind your back.


Recover your lost files quickly

Unforeseen circumstances can happen at any time while using the computer: it can turn off due to a power cut, a Blue Screen of Death (BSoD) can occur, or random Windows updates can the machine when you went away for a few minutes. As a result, your schoolwork, important documents, and other data might be lost. To recover lost files, you can use Data Recovery Pro – it searches through copies of files that are still available on your hard drive and retrieves them quickly.


About the author
Ugnius Kiguolis
Ugnius Kiguolis - The problem solver

Ugnius Kiguolis is the founder and editor-in-chief of UGetFix. He is a professional security specialist and malware analyst who has been working in IT industry for over 20 years.

Contact Ugnius Kiguolis
About the company Esolutions


What you can add more about the problem: "How to fix Windows activation error 0x803FABB8?"