Setup Cannot Locate Toolkit Documentation-x86-en-us.msi Portable Info

The error "Setup cannot locate toolkit documentation-x86-en-us.msi" typically occurs when installing the Windows Assessment and Deployment Kit (ADK). This happens because the installer cannot find a specific component, often due to an incomplete download, restricted folder permissions, or attempting an offline installation without all required files.  1. Perform an Offline Download (Most Reliable) 

The most common cause is a timeout or corruption during a direct online installation. Instead of running the installer directly, download all files first.  Run the adksetup.exe file.

In the Specify Location screen, select "Download the Windows Assessment and Deployment Kit for installation on a separate computer".

Choose a local path (like a folder on your desktop) to save the files.

Once the download completes, go to that folder and run adksetup.exe from there to finish the installation.  2. Check Folder Permissions  setup cannot locate toolkit documentation-x86-en-us.msi

The installer may fail if it doesn't have permission to write to or read from the download directory. 

Change Download Path: Avoid installing directly to system folders or network drives. Try a simple path like C:\ADK_Files.

Run as Administrator: Right-click adksetup.exe and select Run as administrator to ensure it has full system access.

Verify User Rights: Ensure your account has "Back up files and directories" rights, or try installing via the SYSTEM account if you are on a restricted corporate machine.  3. Manually Install the Missing Component  Download the Media Creation Tool for your Windows version

If you have already downloaded the ADK files, you can try to install the specific missing piece manually. 

Navigate to your ADK download folder (often found in Installers or a sub-folder).

Search for the file named toolkit documentation-x86_en-us.msi. Double-click this file to install it individually. After it installs, restart the main adksetup.exe.  4. Download a Fresh Installer 

If the steps above fail, your initial installer file might be corrupt.  Delete your current adksetup.exe. 4. Clear MSI cache & retry

Download the latest version directly from the official Microsoft ADK download page.

Ensure you are downloading the version that matches your Windows OS (e.g., Windows 10 vs. Windows 11).  Install the Windows ADK offline - Microsoft Learn

Method 9: The Nuclear Option – Use the Microsoft Installation Media to Repair the OS

If all else fails, the Windows Installer core files may be damaged. Use the Windows Media Creation Tool to perform an in-place upgrade repair.

1. Download the Media Creation Tool for your Windows version.
2. Run it and select Upgrade this PC now.
3. Choose Keep personal files and apps.
4. Let the process complete. This will replace all system files, including the Windows Installer engine, without erasing your data.
5. After the repair, the MSI error should disappear.

2. Check for Missing Files

• If you have access to another installation of Visual Studio or a similar setup, you can try copying the toolkit documentation-x86-en-us.msi file from there into your installation directory.
• Ensure that you're running the installation process with sufficient permissions (as an administrator).

Method 3: Clean the Windows Installer Cache with a Dedicated Tool

Windows keeps a hidden cache of MSI files at C:\Windows\Installer. Over time, this cache gets bloated or corrupted.

• Warning: Do not manually delete files from this folder. Instead, use Microsoft’s msizap tool (part of the Windows SDK) or a third-party tool like Windows Installer CleanUp Utility (use with extreme caution).
• Recommended approach: Download the Microsoft Program Install and Uninstall Troubleshooter (officially from Microsoft). This tool automatically detects and fixes missing MSI references.

Method 1: The "Show Me Where" Trick (Quickest)

Sometimes the installer allows you to manually point to the missing file.

1. Click Browse on the error dialog.
2. Navigate to the original installation media or folder where the toolkit was installed.
3. Look for a subfolder named redist or msi.
4. Select the file. If you find it, the installation continues.

4. Clear MSI cache & retry

• Run msiexec /unregister followed by msiexec /regserver
• Delete contents of %temp% folder
• Retry installation as Administrator