Getuidx64 Require Administrator Privileges May 2026

Implement a getuidx64 function that retrieves user identity information on 64-bit Windows systems, with explicit enforcement that the calling process must have administrator privileges.

typedef struct 
    wchar_t Domain[256];
    wchar_t UserName[256];
    DWORD SessionId;
    DWORD IntegrityLevel;
    BYTE SID[SECURITY_MAX_SID_SIZE];
    DWORD SIDSize;
 UIDX64_INFO;

When admin privileges are present, the function MUST retrieve: getuidx64 require administrator privileges

Now that you understand the root cause, let's move to solutions. These are ranked from simplest to most complex. Implement a getuidx64 function that retrieves user identity

Use appropriate privileges:

Use a Service / Scheduled Task:

Scope to user-level alternatives:

Least-privilege design:

Error handling:

Audit and logging:

Standard getuid-like functions on Windows don't map directly to POSIX UIDs. This feature provides a native Windows implementation that requires elevated rights to access certain user identity information. When admin privileges are present, the function MUST

If you are a developer porting Unix applications to Windows, you can avoid creating the getuidx64 problem altogether by following best practices:

If you are a developer who wrote (or maintains) an application that throws this error, or if you are comfortable modifying binaries, here is how to resolve getuidx64 permanently.