SecLookupAccountSid function

SecLookupAccountSid accepts a security identifier (SID) as input. It retrieves the name of the account for this SID and the name of the first domain on which this SID is found.


NTSTATUS SecLookupAccountSid(
  _In_      PSID            Sid,
  _Out_     PULONG          NameSize,
  _Inout_   PUNICODE_STRING NameBuffer,
  _Out_     PULONG          DomainSize,
  _Out_opt_ PUNICODE_STRING DomainBuffer,
  _Out_     PSID_NAME_USE   NameUse



A pointer to the SID to look up.


A pointer to a variable that specifies the size of the NameBuffer. On input, this value specifies the size in bytes of the input NameBuffer. If the function fails because the buffer is too small, this variable receives the required buffer size. On success, this variable contains the size of the returned NameBuffer.


A pointer to the NameBuffer.






A pointer to a SID_NAME_USE enumerated type that indicates the type of the account when the function returns.

Return Value

SecLookupAccountSid returns STATUS_SUCCESS on success or one of the following error codes on failure:

Return code Description
An internal error occurred while trying to connect to the Local System Authority (LSA) or the local procedure call (LPC) to the security provider failed.
The process ID associated with the currently executing thread does not match the current process ID.
The buffer size for the NameBuffer or the ReferencedDomain parameter was too small.
The length of the Name parameter exceeded the length allowed in a message to the Local System Authority (LSA).
It was not possible to allocate sufficient memory for a temporary internal buffer used by this function.
The Sid parameter could not be found.
This process has terminated so it is not possible to establish a local procedure call (LPC) connection.


SecLookupAccountSid attempts to find a name for the specified SID by first checking a list of well-known SIDs. If the supplied SID does not correspond to a well-known SID, the function checks built-in and administratively defined local accounts. Next, the function checks the primary domain. Security identifiers not recognized by the primary domain are checked against the trusted domains that correspond to their SID prefixes.

If the function cannot find an account name for the SID, SecLookupAccountSid fails. This can occur if a network time-out prevents the function from finding the name. It also occurs for SIDs that have no corresponding account name, such as a logon SID that identifies a logon session.

In addition to looking up SIDs for local accounts, local domain accounts, and explicitly trusted domain accounts, SecLookupAccountSid can look up SIDs for any account in any domain in the forest, including SIDs that appear only in the SIDhistory field of an account in the forest. The SIDhistory field stores former SIDs of an account that has been moved from another domain. To look up a SID, SecLookupAccountSid queries the global catalog of the forest.

SecLookupAccountSid is equivalent to the Win32 LookupAccountSid function.

SecLookupAccountSid is exported by the ksecdd driver, which implements this function by using user-mode helper services. Accordingly, the use of this function within file systems must obey the usual rules for communication with user-mode services. SecLookupAccountSid cannot be used during paging file I/O.


Windows version This SecLookupAccountSid function is only available on Windows XP and later.
Target Platform Universal
Header ntifs.h (include Ntifs.h)
Library Ksecdd.lib

See Also





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