SetupDiag can help fix Windows 10 upgrade issues – here’s how to use it.

Although Windows 10 usually provides an error code about an upgrade or update failure, sometimes, it won’t show anything leaving you guessing the root of the problem, which can be very frustrating, especially if you’re trying to install a new version of the OS.

However, Microsoft offers an optional tool, known as SetupDiag, which is available for free and designed to diagnose and determine the exact reason an update or upgrade failed to install.

SetupDiag works by analyzing the Windows Setup logs (left behind by the installation process) and checking the information against a database of known issues to determine the reason for the installation failure, which you can use to find a solution for the problem.

At the time of this writing, the SetupDiag tool includes a database (rules.xml) with 60 rules to match known issues, but the rules receive updates as new versions of the tool rollout.

In this Windows 10 guide, we’ll walk you through the steps to use the SetupDiag tool to understand the reason an update or upgrade failed to install to help you find a solution.

How to check Windows 10 upgrade failure using SetupDiag

The process of using SetupDiag is straightforward. You only need to make sure that the required version of the .NET Framework is installed, then run the tool, and review the results.

Confirm .NET Framework version

To confirm that the device meets the minimum .NET Framework requirements, use these steps:

1. Open Start.
2. Search for Command Prompt, right-click the top result, and select the Run as administrator option.
3. Type the following command to reveal the version of .NET installed and press Enter:

   reg query "HKLM\SOFTWARE\Microsoft\Net Framework Setup\NDP\v4" /s

4. Confirm that the “Version” field reads something higher than 4.6.xxxxx, then you can run the tool.

   

   Source: Windows Central

If the device includes .NET 4.6 or higher, then continue with the steps below. Otherwise, download the .NET version 4.6 offline installer, then double-click the file to install the software.

Run SetupDiag tool

To run the SetupDiag tool on Windows 10, use these steps:

1. Open SetupDiag download page.
2. Click the Download SetupDiag button.

   

   Source: Windows Central

3. Select an empty folder to download the files.

   Quick tip: You can always create a new folder using the New folder button from the “Save As” dialog box and name it: “SetupDiag”.

4. Click the Save button.
5. Open File Explorer.
6. Browse to the downloaded file location.
7. Right-click the “SetupDiag.exe” and select the Run as administrator option.

   

   Source: Windows Central

Once you complete the steps, the tool will run immediately without the need of installation or user interaction. It’ll check the available rules against the logs of the failed installation, and the SetugDiag will close automatically.

After the process completes, you’ll end up with three new files, including the “Log.zip,” “SetupDiag.exe.config,” and “SetupDiagResults.log” inside the folder where you downloaded the SetupDiag.exe file.

Understand SetupDiag results

To view and understand the SetupDiag results, use these steps:

1. Open File Explorer.
2. Browse to the downloaded file location.
3. Right-click the SetupDiagResults.log file and select the Open option.

   

   Source: Windows Central

After you complete the steps, the log file will open with the results that the tool was able to identify based on the known rules.

For example, for this guide, we started the upgrade process to a newer version of Windows 10, and then the device was forcedly shutdown. The setup process reverted to the previous version, and error logs were saved on the device.

In the first part of the file, you’ll find some system information about your computer, including device name, manufacturer, BIOS (UEFI) version, the original version of Windows 10, registered antivirus, upgrade date, and more.