Fix Error 0x8007007E in Windows & Office Updates

Encountering error 0x8007007E (ERROR_MOD_NOT_FOUND) during Windows or Microsoft 365 updates is a common issue that can stop updates or break Outlook. This error means a required system file or module is missing, often due to corrupted caches, software conflicts, or interrupted updates.

The Fix

Start with the simplest solutions and proceed to more advanced steps if needed.

Method 1: Basic Troubleshooting

Run the Windows Update Troubleshooter: Settings > System > Troubleshoot > Other troubleshooters. Check your internet connection and temporarily disable any VPN, third-party firewall, or antivirus software (like Trend Micro or Malwarebytes), as these can block Microsoft servers. Install any other pending Windows updates, as a cumulative update may fix the issue.

If That Doesn't Work:

Method 2: Reset Windows Update Components

This often fixes Windows Update and Office update errors. Run these PowerShell commands as Administrator to clear corrupted caches.

# Stop update services
Stop-Service -Name BITS, wuauserv, appidsvc, cryptsvc -Force

Clear the update cache
Remove-Item -Path "C:\Windows\SoftwareDistribution\*" -Recurse -Force
Remove-Item -Path "C:\Windows\System32\catroot2\*" -Recurse -Force

Restart the services
Start-Service -Name BITS, wuauserv, appidsvc, cryptsvc

Restart your PC and try the update again.

If That Doesn't Work:

Method 3: Repair System Files & Microsoft 365

Corrupt system files can cause this error. Run these commands in an Administrator Command Prompt, in order:

DISM /Online /Cleanup-Image /RestoreHealth
sfc /scannow

For Microsoft 365 or Outlook errors, repair the Office installation. Go to Settings > Apps > Apps & features, select Microsoft 365, click Modify, and choose Online Repair. If the error occurs during Outlook sign-in, create a new profile via Control Panel > Mail > Show Profiles.

If That Doesn't Work:

Method 4: Address Specific Software Conflicts

HP Software/Drivers: Uninstall HP support solutions (like software related to hppatusg01.dll) via Settings > Apps and install fresh drivers from HP.
.NET Framework/Visual Studio: Install the latest .NET Framework offline installer as Administrator. For Visual Studio errors, use the Visual Studio Installer to perform a Repair.
WAM Sign-in Issue (Outlook): If the Web Account Manager plugin fails after an update, re-register it in PowerShell (Admin):

Get-AppxPackage Microsoft.AAD.BrokerPlugin | Remove-AppxPackage

Get-AppxPackage Microsoft.AAD.BrokerPlugin | Add-AppxPackage -Register -DisableDevelopmentMode

Verify

The fix is successful when the failed operation completes. For Windows Update, check Settings > Windows Update for a successful install. For Outlook, it should launch and connect without error. If the problem persists, a Repair Upgrade of Windows using a Microsoft ISO is the final in-place repair step that replaces system files while keeping user data.