Topic: robocopy

• Windows exit codes beyond pass/fail: robocopy's bitmask, msiexec's installer codes, and $LASTEXITCODE

  robocopy encodes several independent facts (files copied, extra files, mismatches, failures) into one number below 8 that must be read as a bitmask, not compared to zero; msiexec returns specific Windows Installer codes where 3010 and 1641 mean success with a pending reboot, not failure; and PowerShell's $LASTEXITCODE is the only reliable way to see a native program's real code, with different rules depending on how the script was invoked.

  article · en · reviewed · knowledge as of 2026-09-25

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