Windows Update Error 80240020


The Windows Update utility reportedly fails with 80240020 error in Windows 10 or earlier versions.

Download the Diagnostic

There are certain situations when missing entries in your registry and registry corruption causes this problem. Try running a registry scan to identify if there are any such issues.

  1. Click the button below to download and install the Diagnostic
  2. Perform a Registry scan and fix any problems detected.
  3. Restart your computer.

Estimated Download Time: 10 Seconds

Switch Account

Log in to your machine from the Administrator user account. You may be logged in from a Standard User Account that doesn’t have privileges to install updates which are an administrative process.

For Windows 10:

1. Press Windows Key + X simultaneously.

2. Choose “Shut down or sign out.”


3. Choose “Sign out.”

4. After your account is logged off, sign into Administrator user account with a valid password, if any.

For Windows 8.1/ 8:

1. Click the Start button.

2. Click your user account picture.

3. Select “Sign out.”

4. Sign in with Administrator account.

For Windows 7:

1. Click Start.

2. Point to the arrow next to the Shutdown option.

3. Choose “Log off.”

4. Log-in from an Administrator account.

Verify Required System Services are Not Stopped

Windows Update, Background Intelligent Transfer, and System Event Notification services must be running before starting the update download-install process. Make sure none of these services are stopped; and if ended, restart them again.

For Windows 10/ 8.1/ 8/ 7/ Vista:

1. Press Windows Key + R to open Run.

2. Type “Services.msc”, and click OK. (Right click > Start)


3. Start the services mentioned below:

  • Background Intelligent Transfer Service
  • System Event Notification Service
  • Windows Update


4. Exit out of the window; reboot your machine.

Check Problems about Name Resolution

Make sure you’ve set a valid name resolution.

For Windows 10/ 8.1/ 8:

1. Open Run dialog.

2. Type “sysdm.cpl” and press ENTER.


3. Click Change button under Computer Name tab.

4. Note down your Computer Name.

5. Exit opened dialogs.

6. Press Windows Key + X; choose Command Prompt (Admin).

7. One by one execute below commands:

  • Nslookup
  • Ns
  • <type your computer name>


8. Now you should see the DNS (Domain Name Server) IP Address.

9. Retry downloading and installing the Windows Updates.

For Windows 7/ Vista:

1. Refer Steps # 1-5 from Windows 10/ 8.1/ 8 section.

2. Open Command Prompt. To do so, type “CMD” in the Search Box of your Start Menu.

3. When “Command Prompt” is displayed in Search Results, right-click it and choose Run as administrator.

4. Refer Steps # 7-9 from Windows 10/ 8.1/ 8 section.

Re-download Software Distribution Content

The content downloaded to SoftwareDistribution folder may have corrupted. Do not delete the “Download” folder; only delete its contents.

For Windows 10/ 8.1/ 8/ 7/ Vista:

1. Open File Explorer through its Taskbar icon (in the case of Windows 10). Open My Computer, in the case of an earlier version of Windows.

2. Open following directory:

  • C:\Windows\SoftwareDistribution\Download\

3. Empty the contents of “Download” subfolder.


4. Open Command Prompt.

5. Run the following command:

  • Wuauclt.exe /updatenow

6. Exit; restart.

Allow OS Upgrade

There’s a string named AllowOSUpgrade in the Windows Update Registry entries. Make sure appropriate subkey, and string exists and enabled.

For Windows 10/ 8.1/ 8/ 7/ Vista:

1. Open Registry Editor. (Run > RegEdit)

2. Locate the following subkey:

  • HKEY_LOCAL_MACHINE | SOFTWARE | Microsoft | Windows | CurrentVersion | WindowsUpdate | OSUpgrade

If no such subkey is found, create a new one. Click the Edit menu, choose New | Key. Specify the name “OSUpgrade,” and press ENTER.


3. Double click “AllowOSUpgrade” DWORD (32-bit) Value. If it doesn’t exist, create a new one. Click Edit | New | DWORD (32-bit) Value. Type the name “AllowOSUpgrade.”


4. Ensure “AllowOSUpgrade” contains “1” value.

5. Close the window; restart.

Troubleshoot Windows Update Components

Windows come with a pre-installed tool that detects and repairs the problem with the Windows Update utility. The tool, named as Troubleshooter, requires administrative privileges and automatically fixes Windows Update error 80240020. The steps are given as under:

For Windows 10:

1. In the Search Box on your Taskbar, type “Troubleshooting.”


2. Open that keyword from Search Results.

3. Click System and Security | Windows Update.


4. It automatically searches for problems, resolves them and might require a system reboot as well.


For Windows 8.1/ 8:

1. Open Start Screen.

2. Type “Troubleshooting” in the Search Box.

3. Click Settings icon.

4. Open that from Search Results.

5. Refer Steps # 3-4 under Windows 10 section.

For Windows 7/ Vista:

You may need to obtain standalone Windows Update Troubleshooter from Microsoft Download Center. Use the Search box.

1 Comment

  1. Braulio

    sorry to say but if your using XP, defragmenting your hard drive won’t do anhiytng for your systems speed. The reason why is that XP saves everything on the hard drive fragmented thats how it works. If your using a FAT32 hard drive defragmenting will speed up the system but XP on a Sata hard drive will not.

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