[Bug]: Windows Sandbox Fails to Start with an Error Code: 0x800705B4

### Windows Sandbox version 0.5.3 ### Windows build number 10.0.26200.7309 ### Other software _No response_ ### Steps to reproduce the bug 1. Uninstall Windows Sandbox from Windows Features in Control Panel. 2. Reinstall Windows Sandbox from Windows Features in Control Panel. 3. Start Windows Sandbox. 4. Windows Sandbox will be updated to the latest version. 5. Windows Sandbox logo will stall with a spinning circle for ten minutes or so. 6. An error code will show: 0x800705B4. ### Expected result Windows Sandbox is supposed to start after seeing a logo for three or five seconds. ### Actual result Windows Sandbox logo will stall for ten minutes or so and an error code, 0x800705B4, will pop up. In C:\ProgramData\Microsoft\Windows\Containers\ContainerStorages, if I double-click a GUID (for example, ab243dfa-20dl-2k33-hjg8-2934hb767yh4), a sandbox.vhdx file will grow up to 1GB. After this, it gets deleted and Windows Sandbox exits with a 0x800705B4 error code. ### Included System Information _No response_

Posted by CompactProducer on Dec 5, 2025, 3:39 PM

Tags

• github (SaaS)

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