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0x800F081FSystemHigh

Error 0x800F081F — Source Missing (CBS_E_SOURCE_MISSING) | Windows System Error Fix

Windows 11Windows 10Windows Server 2022

What Does 0x800F081F Mean?

The source files could not be found. The component store does not have the required files to enable the feature.

Real-World Causes

  1. 1Trying to enable .NET Framework 3.5 without installation media
  2. 2Component store is corrupted and missing source files
  3. 3Group Policy restricting download from Windows Update
  4. 4WSUS server does not have the required feature files

Symptoms

  • ⚠Cannot enable Windows features like .NET Framework 3.5
  • ⚠DISM operations fail with source missing error
  • ⚠Windows Optional Features installation fails
  • ⚠Error 0x800F081F in Programs and Features

DIY Fix

Beginner-friendly steps you can try at home

  1. 1Enable .NET Framework 3.5 using Windows installation media: 'DISM /Online /Enable-Feature /FeatureName:NetFx3 /All /Source:D:\Sources\sxs'
  2. 2Use Windows Update as the source: Settings > Apps > Optional Features > install from there
  3. 3Run 'DISM /Online /Cleanup-Image /RestoreHealth' to repair the component store first

Advanced Fix

For experienced users and IT professionals

  1. 1Check Group Policy: Computer Configuration > Administrative Templates > System > Specify settings for optional component installation > enable 'Download repair content from Windows Update'
  2. 2For WSUS environments, temporarily point to Windows Update: 'Set Group Policy to allow WU access or use /LimitAccess:False'

Frequently Asked Questions

Why can't Windows find the .NET Framework 3.5 source?
Windows 10/11 includes .NET 3.5 as an optional feature but needs source files to install it. These can come from Windows Update or installation media. If Group Policy blocks Windows Update access (common in enterprises), you must provide the source manually using a Windows ISO.

Related Error Codes

0x800F0831Store Corruption Detected (CBS_E_STORE_CORRUPTION_DETECTED)0x80070490Element Not Found (ERROR_NOT_FOUND)

About the Author

Windows Troubleshooting Team

Verified against official Microsoft documentation and real-world diagnostic data. Error behavior confirmed across Windows 10, Windows 11, and Windows Server.