Hello guys, Microsoft kept releasing and retracting the October 2018 update but finally it’s somewhat official. You can find all the details in our Latest Windows Update guide.

But I know what brings you here: it’s the 0x800F081F – 0x20003 error which appears when you try to update your Windows to the October version. I myself got that error and I managed to fix it and I’d like to help you with that too.

The reason behind this error is that you have Developer mode On, therefore, the solution is to turn it off temporarily, uninstall its Windows component and after updating Windows, turn it back on (if still needed).

So let’s not waste time and go straight to the solution!

Step I: Turn Developer mode Off

  1. Click on the gear icon in your Start menu in order to launch the Settings.
  2. Click on Update & Security.
  3. Choose For developers from the left pane and in your case, your developer mode option will be checked, we need to change that to Sideload apps.
  4. Click Yes in order to confirm changing modes.
  5. Now that we changed our setting, let’s uninstall a small Windows component special for developer mode so that we are sure this mode will not interfere with our update. Go to back to your Settings homepage and choose Apps.
  6. Make sure you’re on in the App & Features tab from the left pane and click Manage optional features.
  7. Scroll down till you find Windows Developer Mode, click on it and then choose Uninstall.
  8. Wait for a while until the Windows Developer Mode disappears from the list.

Now you’re ready for updating your Windows. Follow the next section in order to download the latest build using Windows 10 Update Assistant.

Step II: Use Windows 10 Update Assistant

I myself couldn’t find any available updates when I used the traditional check for updates button in the Settings app. I had to use the other way to check for updates which is the Windows 10 Update Assistant, which displays more details during the Updating process. Let’s do it together:

  • Go to https://www.microsoft.com/en-us/software-download/windows10 and click on the Update now button.
  • A light program will be downloaded to your computer, it’s the Windows 10 Update Assistant.
  • Open the program and click Yes.
  • You’ll see an icon appearing on your desktop named Windows 10 Update Assistant. Double-click on it to start using the assistant.
  • Here, you’ll see the latest version available to download. Time to click Update Now.
  • If your CPU, Memory, Disk space are okay, click Next.
  • Downloading updates will start, just wait for them to finish, and then your computer should be restarted automatically or manually, so keep an eye on it.

Now you do have the latest Windows 10 build, and if you want to turn developer mode back on, just go back to Step I and change your choice to Developer mode.

I hope that solved your problem! If it didn’t, please let me know in the comments below or in the forum and we’ll try to solve it together.