Microsoft Store version fails to launch: conflicting desktop6:FileSystemWriteVirtualization and virtualization:FileSystemWriteVirtualization namespace declarations in AppxManifest.xml cause AppX activation failure (0x80072EFD)
What version of the Codex App are you using (From “About Codex” dialog)?
26.513.4821.0
What subscription do you have?
plus
What platform is your computer?
Microsoft Windows NT 10.0.22631.0 x64
What issue are you seeing?
Description
After installing Codex from the Microsoft Store, clicking "Launch" from the Start Menu or Store produces no response at all — no window appears, no error message is shown. However, running Codex.exe directly works fine.
Environment
OS: Windows 11 Pro (Build 22631, version 2009)
App: OpenAI.Codex (Microsoft Store)
Windows Event Log
Every launch attempt triggers the following error in Microsoft-Windows-AppModel-Runtime/Admin:
Event ID: 203
Level: Error
Message: 0x80072EFD: Failed to launch process for package OpenAI.Codex_26.513.4821.0_x64__2p2nqsd0c76g0
because the process to prepare the virtual machine failed. [LaunchProcess]
Root Cause
There is a conflicting namespace declaration in AppxManifest.xml:
<Properties>
<!-- desktop6 namespace: disables file system virtualization -->
<desktop6:RegistryWriteVirtualization>disabled</desktop6:RegistryWriteVirtualization>
<desktop6:FileSystemWriteVirtualization>disabled</desktop6:FileSystemWriteVirtualization>
<!-- virtualization namespace: yet configures excluded directories,
contradicting the 'disabled' above -->
<virtualization:FileSystemWriteVirtualization>
<virtualization:ExcludedDirectories>
<virtualization:ExcludedDirectory>$(KnownFolder:LocalAppData)\OpenAI</virtualization:ExcludedDirectory>
</virtualization:ExcludedDirectories>
</virtualization:FileSystemWriteVirtualization>
<virtualization:RegistryWriteVirtualization>
<virtualization:ExcludedKeys>
<virtualization:ExcludedKey>HKEY_CURRENT_USER\Software\Google\Chrome\NativeMessagingHosts</virtualization:ExcludedKey>
</virtualization:ExcludedKeys>
</virtualization:RegistryWriteVirtualization>
</Properties>
The desktop6 namespace declares FileSystemWriteVirtualization = disabled, but the virtualization namespace simultaneously defines ExcludedDirectories. These two declarations are contradictory, causing the AppX runtime to fail when preparing the package container ("virtual machine").
Workaround
Run the executable directly to bypass the AppX container:
C:\Program Files\WindowsApps\OpenAI.Codex_26.513.4821.0_x64__2p2nqsd0c76g0\app\Codex.exe
Suggested Fix
Pick one:
Option A: Since desktop6:FileSystemWriteVirtualization=disabled already disables virtualization, remove the redundant virtualization:FileSystemWriteVirtualization and virtualization:RegistryWriteVirtualization elements entirely.
Option B: Use a consistent approach — switch to the virtualization namespace exclusively to enable virtualization with exclusions, and remove the desktop6 disabled declarations.
What steps can reproduce the bug?
- Install Codex from the Microsoft Store on Windows 11 Build 22631
- Click the Codex icon in Start Menu, or click "Launch" from the Store
- Nothing happens
What is the expected behavior?
_No response_
Additional information
_No response_