SIDCHG is a dedicated third-party command-line utility created by Stratesave used to modify the local Security Identifier (SID) of a Windows machine. Historically, duplicate SIDs on a network were mostly a minor annoyance. However, recent Windows security modifications (such as those introduced in the late 2025 monthly updates) actively check for duplicate SIDs. If identical SIDs are found on cloned production machines, Windows will outright deny access to Remote Desktop (RDP) and file sharing between those devices.