Fixing Windows Upgrade Errors: Solutions for 0x8007002C, 0x80246007, 0x80070004, & 0x80240020

Updated: 19 May, 2025 • 0 • min read

Table of Contents

Fixing Windows Upgrade Errors

Encountering error codes during a Windows 11 or Windows 10 upgrade can be frustrating, halting the process unexpectedly. Four common errors that users frequently face are 0x8007002C, 0x80246007, 0x80070004, and 0x80240020. While these codes might seem distinct, they often point to underlying issues within the Windows Update process, frequently related to corrupted or incomplete download files residing in the Software Distribution folder, or problems with the system image itself. Fortunately, several effective methods can be employed to diagnose and fix these specific upgrade impediments, allowing you to successfully continue with your Windows installation or update.

Before initiating any troubleshooting steps, it’s prudent to perform a few preparatory actions to minimize potential conflicts. Temporarily disabling your security software, such as antivirus or firewall applications, can prevent them from interfering with the upgrade files or process. Disconnecting non-essential peripherals like printers, external hard drives, or USB devices can also eliminate potential hardware conflicts. Ensure your computer is connected directly to a reliable power source, especially for laptops, to prevent unexpected shutdowns during critical operations. Finally, verify that you have a stable internet connection.

Method 1: Clearing the Windows Update Cache¶

One of the most frequent culprits behind these specific upgrade errors is corrupted or incomplete data within the Windows Update cache. This cache is stored in the Software Distribution folder, which Windows uses to download and prepare update files. Cleaning out the contents of this folder forces Windows Update to download fresh copies of the necessary files, often resolving issues related to faulty downloads.

Steps to Clear Software Distribution Folder¶

To effectively clear the cache, you typically need to stop the Windows Update service and the Background Intelligent Transfer Service (BITS) first. These services manage the download and installation of updates, and stopping them ensures the files within the Software Distribution folder are not actively in use, allowing for their deletion.

Open Command Prompt as an administrator. You can do this by searching for “cmd” in the Start menu, right-clicking on “Command Prompt,” and selecting “Run as administrator.”
Once the administrative Command Prompt window is open, type the following commands one by one, pressing Enter after each:
```
net stop wuauserv
net stop bits
net stop cryptsvc
net stop msiserver
```
These commands stop the Windows Update Service (wuauserv), the Background Intelligent Transfer Service (bits), the Cryptographic Services (cryptsvc), and the Windows Installer Service (msiserver). You should receive a message confirming that each service was stopped successfully.
Now, open File Explorer and navigate to the C:\Windows\SoftwareDistribution folder.
Inside the SoftwareDistribution folder, delete all files and folders. You might encounter prompts asking for administrator permission; confirm these if necessary. Do not delete the SoftwareDistribution folder itself, only its contents. If some files cannot be deleted because they are in use, restart your computer and try the steps again, or ensure the services stopped correctly.
After deleting the contents, return to the administrative Command Prompt window.
Restart the services you stopped earlier by typing the following commands and pressing Enter after each:
```
net start wuauserv
net start bits
net start cryptsvc
net start msiserver
```
You should receive confirmation that each service started successfully.
Optionally, you can now trigger an immediate check for updates using the command prompt. While not strictly necessary after restarting services and clearing the cache, it can sometimes prompt the system to begin the download process immediately. In the administrative Command Prompt, execute:
```
wuauclt.exe /updatenow
```
This command tells the Windows Update client to check for updates.
Close the Command Prompt window and open Windows Settings. Navigate to the Update & Security (or Windows Update) section and click “Check for updates.” Windows should now begin detecting and downloading the necessary upgrade files again, hopefully without encountering the previous errors.

Ensuring Sufficient Disk Space¶

A critical requirement for a successful upgrade is adequate free space on your system drive (usually C:). Upgrade files can be quite large, and the process requires additional space for temporary files, migrating user data, and creating recovery partitions. Insufficient disk space can cause downloads to fail or the installation process to stall, leading to errors like those mentioned.

To check your available disk space, open File Explorer, click on “This PC,” and look at the drive where Windows is installed (usually C:). It will show the total size and free space. Microsoft provides guidelines on the minimum required space for upgrades, but having significantly more than the minimum is always recommended for a smoother process.

If you are low on disk space, consider using the built-in Disk Cleanup utility. Search for “Disk Cleanup” in the Start menu, select your system drive, and let it scan. Check the boxes next to temporary files, previous Windows installations (if applicable), delivery optimization files, and other items you no longer need. Click “Clean up system files” for more options, including cleaning up Windows Update Cleanup files.

Alternatively, if your C: drive is persistently full and you have other drives with ample space, you might consider relocating certain user folders or libraries (like Documents, Downloads, Pictures) to a different drive before attempting the upgrade. While Windows Update doesn’t officially support changing its download location easily for major upgrades, ensuring your C: drive is as clear as possible is vital. For significant space constraints, consider using external storage during the upgrade process if prompted by the upgrade tool, or even performing a clean install from external media if other methods fail.

Method 2: Repairing the System Image with DISM and SFC¶

Errors during an upgrade, especially codes like 0x80070004 (which can relate to migration issues) and others, can sometimes be a symptom of underlying corruption within the Windows system image or its core files. The Deployment Image Servicing and Management (DISM) tool is designed to service a Windows image or prepare a Windows Preinstallation Environment (Windows PE) image, but it’s also invaluable for repairing your current Windows installation. Following a DISM scan and repair, running the System File Checker (SFC) tool is a standard practice to fix any remaining corrupted system files.

Using the DISM Tool¶

DISM can check the health of the Windows component store, which is the source for Windows updates and system repairs. If this store is corrupted, it can lead to various update and upgrade failures. Running DISM with the correct parameters attempts to fix these issues using files from the component store itself or, if necessary, from an external source.

Open Command Prompt as an administrator (as described in Method 1).
Start by checking the health of the image. Type the following command and press Enter:
```
Dism /Online /Cleanup-Image /CheckHealth
```
This command performs a quick check to see if any corruption flags are present in the image.
Next, perform a more thorough scan of the image. Type:
```
Dism /Online /Cleanup-Image /ScanHealth
```
This command scans the component store for corruption and records any findings in the CBS.log file. This scan can take several minutes to complete.
If CheckHealth or ScanHealth indicate issues, or even if they don’t but you suspect image corruption, run the RestoreHealth command. This command attempts to repair the image using files from the component store or Windows Update. Type:
```
Dism /Online /Cleanup-Image /RestoreHealth
```
This process can also take significant time depending on the level of corruption and system speed. It requires an internet connection as it often downloads replacement files from Windows Update.

Using a Repair Source: In some cases, especially if the Windows Update client itself is broken or the corruption is severe, DISM might report that it couldn’t find the source files needed for the repair. When this happens, you need to provide an external source, such as installation media (a mounted ISO file or a USB installation drive) from the same version and build of Windows you are trying to repair.

To use an external source, you would modify the RestoreHealth command. First, mount your Windows ISO file by double-clicking it in File Explorer, or connect your USB installation drive. Note the drive letter assigned to the mounted media (e.g., D:, E:). The source files are typically located in the \sources folder, specifically the install.wim or install.esd file.

The command structure to use a source is:
```
DISM.exe /Online /Cleanup-Image /RestoreHealth /Source:WIM:<path to install.wim or install.esd>:1 /LimitAccess
```
Replace <path to install.wim or install.esd> with the actual path on your mounted media. For example, if your mounted ISO is drive D: and contains install.wim in the sources folder, the path would be D:\sources\install.wim. The :1 after the WIM file path specifies the Windows image index to use (typically 1 for standard Windows editions). The /LimitAccess switch prevents DISM from using Windows Update as a repair source, forcing it to use only the specified external source.

For example:
```
DISM.exe /Online /Cleanup-Image /RestoreHealth /Source:WIM:D:\sources\install.wim:1 /LimitAccess
```
Adjust the drive letter and file extension (.wim or .esd) based on your installation media. This process will use the healthy files from your installation media to repair the corrupt ones in your current system image.
After running the appropriate DISM command (RestoreHealth with or without a source), restart your computer.

Using the System File Checker (SFC) Tool¶

The SFC tool scans and replaces corrupted, lost, or changed system files with correct versions. While DISM fixes the Windows image used as a source for system repairs, SFC specifically checks and repairs the files currently running on your system. It’s best practice to run SFC after running DISM, as DISM ensures SFC has a healthy source to pull from if needed.

Open Command Prompt as an administrator.
Type the following command and press Enter:
```
sfc /scannow
```
This command will scan all protected system files and replace corrupted files with a cached copy. Do not close the command prompt window until the verification is 100% complete.
SFC might report that it found no integrity violations, found violations and fixed them, found violations but was unable to fix some, or could not perform the operation. If it reports issues it couldn’t fix, you might need to run SFC in Safe Mode or consult the CBS.log file for details.
After SFC completes, restart your computer again.

With the Windows component store and core system files potentially repaired, attempt the Windows upgrade again through Settings > Update & Security.

Method 3: Specific Fix for Error 0x80240020¶

Error code 0x80240020 is often documented as an expected error message that indicates the upgrade requires user action or is waiting for certain conditions to be met before proceeding. While frustrating, it doesn’t always signify a severe problem. However, if the upgrade doesn’t continue on its own after some time, a specific registry modification has been found to help nudge the process along. This tweak can sometimes force the Windows Update client to proceed with the upgrade download and installation.

Modifying the Windows Registry¶

Important Warning: The Windows Registry is a critical database containing configuration settings for your operating system and installed programs. Incorrectly modifying the registry can cause serious system instability or render your computer inoperable. It is strongly recommended that you back up your registry before making any changes.

To back up the registry, open the Registry Editor (search for regedit in the Start menu). Click “File” > “Export.” Choose a location to save the file (e.g., your Documents folder), select “All” under Export range, give it a descriptive name (like “RegistryBackup_date”), and click “Save.” You can restore this backup later by opening the Registry Editor and selecting “File” > “Import.”

Now, proceed with the modification for error 0x80240020:

Open the Registry Editor by searching for regedit in the Start menu and clicking on the result. You may need to grant administrator permission.
Navigate to the following registry key in the left-hand pane:
```
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\WindowsUpdate
```
You can expand the folders by clicking the arrow next to each key or copy and paste the path into the address bar at the top (available in newer versions of Regedit).
In the left-hand pane, right-click on the WindowsUpdate key (the folder icon).
Select “New” > “Key.”
Name the new key OSUpgrade and press Enter.
Now, select the newly created OSUpgrade key in the left pane.
In the right-hand pane (the empty space), right-click anywhere.
Select “New” > “DWORD (32-bit) Value.”
Name the new DWORD value AllowOSUpgrade and press Enter.
Double-click on the AllowOSUpgrade DWORD you just created.
A small window will open. In the “Value data” field, enter 1. Ensure “Base” is set to “Hexadecimal.”
Click “OK.”
Close the Registry Editor.
Restart your computer for the changes to take effect.

After restarting, open Windows Settings, go to Update & Security (or Windows Update), and check for updates again. The presence of the AllowOSUpgrade DWORD with a value of 1 in the registry tells Windows Update that an OS upgrade is permitted and may help bypass the condition that was causing the 0x80240020 error.

Additional Troubleshooting Steps¶

If the methods above don’t resolve your specific upgrade error, there are other general troubleshooting steps worth trying, as these errors can sometimes be triggered by broader system issues.

Run the Windows Update Troubleshooter¶

Microsoft provides a built-in troubleshooter specifically designed to detect and fix common problems with Windows Update. This tool can often automatically resolve issues related to corrupted files, incorrect settings, or problems with update services.

Open Windows Settings.
Navigate to Update & Security > Troubleshoot (or System > Troubleshoot > Other troubleshooters in Windows 11).
Find “Windows Update” in the list and click “Run the troubleshooter.”
Follow the on-screen instructions and allow the tool to scan for and attempt to fix problems.
Once complete, restart your computer and try the upgrade again.

Perform a Clean Boot¶

Third-party software, especially security programs or system utilities, can sometimes interfere with the Windows upgrade process. Performing a clean boot starts Windows with a minimal set of drivers and startup programs, helping to rule out software conflicts.

Search for “msconfig” in the Start menu and open “System Configuration.”
Go to the “Services” tab. Check the box that says “Hide all Microsoft services” to avoid disabling critical system functions.
Click “Disable all.”
Go to the “Startup” tab and click “Open Task Manager.”
In Task Manager, disable each startup item one by one by right-clicking on it and selecting “Disable.” Close Task Manager.
Back in the System Configuration window, click “Apply” and then “OK.”
You will be prompted to restart your computer. Click “Restart.”

After the clean boot, attempt the Windows upgrade again. If it succeeds, a third-party program was likely the cause. You can then re-enable startup items and services gradually to identify the conflicting software. Remember to return to System Configuration and select “Normal startup” once you are finished troubleshooting.

Check System Logs¶

For more detailed information about why an upgrade failed, the Event Viewer can provide valuable clues. Error events related to Windows Update or the upgrade process are often logged here.

Search for “Event Viewer” in the Start menu and open it.
Navigate to “Windows Logs” > “System” or “Windows Logs” > “Application.”
Look for error or warning events around the time you attempted the upgrade. Pay attention to events related to “Windows Update,” “UpgradeAnalytics,” “Setup,” or “Service Control Manager” that indicate failures.
Double-clicking an event opens a window with more details, including specific error codes and descriptions that might help pinpoint the exact issue.

Use the Media Creation Tool or Update Assistant¶

If relying on Windows Update through Settings consistently fails, consider using alternative methods provided by Microsoft for upgrading. The Media Creation Tool or the Windows 10 Update Assistant (or Windows 11 Installation Assistant) can perform a more direct, and sometimes more robust, upgrade process.

These tools download the full installation files and guide you through the upgrade, offering an option to keep your files and applications. This method bypasses the standard Windows Update process in Settings and can often overcome issues related to its cache or services.

Conclusion¶

Resolving Windows upgrade errors like 0x8007002C, 0x80246007, 0x80070004, and 0x80240020 often involves addressing issues with the Windows Update cache, repairing potential system file corruption, or implementing specific fixes like the registry modification for 0x80240020. By systematically applying the methods outlined above—starting with clearing the update files, using DISM and SFC, and considering the registry tweak—you significantly increase your chances of overcoming these common obstacles. Remember to perform preliminary checks, ensure sufficient disk space, and utilize additional troubleshooting steps like the Windows Update Troubleshooter or clean boot if the initial fixes are unsuccessful. If all else fails, using Microsoft’s Media Creation Tool or Installation Assistant offers a reliable alternative for performing the upgrade.

Have you encountered these errors before? Which method worked for you, or do you have other tips that helped resolve similar Windows upgrade issues? Share your experiences and insights in the comments below to help others facing the same challenges!

cognitive-diss