[BUG] Claude Desktop (Windows MSIX) — MSIX registry silo prevents all C:\Windows\System32\OpenSSH\ binaries from executing in child processes

[Promithius-DR]

Claude Desktop's MSIX packaging on Windows creates a registry silo that prevents Windows System OpenSSH binaries from initializing in any child process spawned by the app. All four binaries in C:\Windows\System32\OpenSSH\ (ssh.exe, ssh-add.exe, ssh-keygen.exe, scp.exe) silently exit with code 255 and produce zero output — including ssh -V, which requires no network connection. Other System32 binaries and Git's bundled OpenSSH work normally from the same child processes.

This breaks any MCP server or workflow that relies on Windows System OpenSSH for remote server management.

bug-report-final.md
bug-report-steps.md
procmon_ssh.CSV
ssh_msix_test.js