Purpose: NSSM runs an application as a Windows service, monitors it, and can restart it if it exits.
Service setup: It provides a graphical interface for installing and removing services, and its command-line options can configure services from scripts.
Exit behavior: When an application exits, NSSM can restart it, ignore the exit, exit itself, or exit uncleanly to trigger service recovery actions.
Logging and I/O: NSSM logs its progress to the Windows system Event Log and can redirect the monitored application's input and output.
Output rotation: NSSM can rotate output files when they reach a configurable size, including while the application is running.
Other controls: NSSM can set an application's priority class and CPU affinity, and can start, stop, and query services.
License: NSSM is public domain and may be used with its source code for any purpose.
Release status: The page lists version 2.24, dated 2014-08-31, as the latest release and a 2.24 prerelease build dated 2017-04-26.
Security and privileges: NSSM requires administrator access to manage services, and the site warns that bugs can cause severe system issues.
Known issues: The bugs page lists version 2.24 issues affecting newer Windows service startup, Windows XP crashes, log rotation over 4 GB, and other cases.
Support: The site directs users to the Windows Application Event Log for troubleshooting and to the author's email address in repository commits to report bugs.
Build and distribution: The site says NSSM is built with Jenkins and that its Chocolatey package is maintained by a third party and may not match the latest site build.
Maker: The NSSM site identifies Iain Patterson as its author.
Price from: Free

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Sources

nssm.cc· checked 4 Oct 2026
nssm.cc/description· checked 4 Oct 2026
nssm.cc/download· checked 4 Oct 2026
nssm.cc/builds· checked 4 Oct 2026
nssm.cc/bugs· checked 4 Oct 2026