diff --git a/Windows API/GetCurrentUserSid.cpp b/Windows API/GetCurrentUserSid.cpp
new file mode 100644
index 0000000..75ab654
--- /dev/null
+++ b/Windows API/GetCurrentUserSid.cpp	
@@ -0,0 +1,167 @@
+/*
+hToken can be NULL
+DisposeProcessHandle closes hToken automatically
+if DisposeProcessHandle is FALSE you need to close it yourself
+The value returned by this function needs to be freed with HeapFree
+*/
+LPWSTR GetCurrentUserSidW(HANDLE hToken, BOOL DisposeProcessHandle)
+{
+	typedef BOOL(WINAPI* CONVERTSIDTOSTRINGSIDW)(PSID, LPWSTR*);
+	CONVERTSIDTOSTRINGSIDW ConvertSidToStringSidW;
+	PSID Sid = NULL;
+	PTOKEN_GROUPS TokenGroup = NULL;
+	DWORD dwError = ERROR_SUCCESS, dwIndex = ERROR_SUCCESS;
+	BOOL bFlag = FALSE;
+	LPWSTR pSid = NULL;
+	HMODULE hAdvapi = NULL;
+
+	hAdvapi = LoadLibraryW(L"Advapi32.dll");
+	if (hAdvapi == NULL)
+		goto EXIT_ROUTINE;
+
+	ConvertSidToStringSidW = (CONVERTSIDTOSTRINGSIDW)RfGetProcAddressA((DWORD64)hAdvapi, "ConvertSidToStringSidW");
+	if (!ConvertSidToStringSidW)
+		goto EXIT_ROUTINE;
+
+	if (!OpenProcessToken(RfGetCurrentProcess(), TOKEN_ALL_ACCESS, &hToken))
+		return NULL;
+
+	dwError = GetTokenInformationBufferSize(hToken);
+	if (dwError == 0)
+		goto EXIT_ROUTINE;
+
+	TokenGroup = (PTOKEN_GROUPS)HeapAlloc(RfGetProcessHeap(), HEAP_ZERO_MEMORY, dwError);
+	if (TokenGroup == NULL)
+		goto EXIT_ROUTINE;
+
+	if (!GetTokenInformation(hToken, TokenGroups, (LPVOID)TokenGroup, dwError, &dwError))
+		goto EXIT_ROUTINE;
+
+	for (; dwIndex < TokenGroup->GroupCount; dwIndex++)
+	{
+		if ((TokenGroup->Groups[dwIndex].Attributes & SE_GROUP_LOGON_ID) == SE_GROUP_LOGON_ID)
+		{
+			if (!IsValidSid(TokenGroup->Groups[dwIndex].Sid))
+				continue;
+
+			dwError = GetLengthSid(TokenGroup->Groups[dwIndex].Sid);
+
+			Sid = (PSID)HeapAlloc(RfGetProcessHeap(), HEAP_ZERO_MEMORY, dwError);
+			if (Sid == NULL)
+				goto EXIT_ROUTINE;
+
+			if (!CopySid(dwError, Sid, TokenGroup->Groups[dwIndex].Sid))
+				goto EXIT_ROUTINE;
+
+			if (!ConvertSidToStringSidW(Sid, &pSid))
+				goto EXIT_ROUTINE;
+			else
+				break;
+		}
+	}
+
+	bFlag = TRUE;
+
+EXIT_ROUTINE:
+
+	if (!bFlag)
+		dwError = EhGetLastError();
+
+	if (TokenGroup)
+		HeapFree(RfGetProcessHeap(), HEAP_ZERO_MEMORY, TokenGroup);
+
+	if (Sid)
+		HeapFree(RfGetProcessHeap(), HEAP_ZERO_MEMORY, Sid);
+
+	if (hAdvapi)
+		FreeLibrary(hAdvapi);
+
+	if (DisposeProcessHandle)
+	{
+		if (hToken)
+			CloseHandle(hToken);
+	}
+
+	return (bFlag ? pSid : NULL);
+}
+
+LPSTR GetCurrentUserSidA(HANDLE hToken, BOOL DisposeProcessHandle)
+{
+	typedef BOOL(WINAPI* CONVERTSIDTOSTRINGSIDA)(PSID, LPSTR*);
+	CONVERTSIDTOSTRINGSIDA ConvertSidToStringSidA;
+	PSID Sid = NULL;
+	PTOKEN_GROUPS TokenGroup = NULL;
+	DWORD dwError = ERROR_SUCCESS, dwIndex = ERROR_SUCCESS;
+	BOOL bFlag = FALSE;
+	LPSTR pSid = NULL;
+	HMODULE hAdvapi = NULL;
+
+	hAdvapi = LoadLibraryW(L"Advapi32.dll");
+	if (hAdvapi == NULL)
+		goto EXIT_ROUTINE;
+
+	ConvertSidToStringSidA = (CONVERTSIDTOSTRINGSIDA)RfGetProcAddressA((DWORD64)hAdvapi, "ConvertSidToStringSidA");
+	if (!ConvertSidToStringSidA)
+		goto EXIT_ROUTINE;
+
+	if (!OpenProcessToken(RfGetCurrentProcess(), TOKEN_ALL_ACCESS, &hToken))
+		return NULL;
+
+	dwError = GetTokenInformationBufferSize(hToken);
+	if (dwError == 0)
+		goto EXIT_ROUTINE;
+
+	TokenGroup = (PTOKEN_GROUPS)HeapAlloc(RfGetProcessHeap(), HEAP_ZERO_MEMORY, dwError);
+	if (TokenGroup == NULL)
+		goto EXIT_ROUTINE;
+
+	if (!GetTokenInformation(hToken, TokenGroups, (LPVOID)TokenGroup, dwError, &dwError))
+		goto EXIT_ROUTINE;
+
+	for (; dwIndex < TokenGroup->GroupCount; dwIndex++)
+	{
+		if ((TokenGroup->Groups[dwIndex].Attributes & SE_GROUP_LOGON_ID) == SE_GROUP_LOGON_ID)
+		{
+			if (!IsValidSid(TokenGroup->Groups[dwIndex].Sid))
+				continue;
+
+			dwError = GetLengthSid(TokenGroup->Groups[dwIndex].Sid);
+
+			Sid = (PSID)HeapAlloc(RfGetProcessHeap(), HEAP_ZERO_MEMORY, dwError);
+			if (Sid == NULL)
+				goto EXIT_ROUTINE;
+
+			if (!CopySid(dwError, Sid, TokenGroup->Groups[dwIndex].Sid))
+				goto EXIT_ROUTINE;
+
+			if (!ConvertSidToStringSidA(Sid, &pSid))
+				goto EXIT_ROUTINE;
+			else
+				break;
+		}
+	}
+
+	bFlag = TRUE;
+
+EXIT_ROUTINE:
+
+	if (!bFlag)
+		dwError = EhGetLastError();
+
+	if (TokenGroup)
+		HeapFree(RfGetProcessHeap(), HEAP_ZERO_MEMORY, TokenGroup);
+
+	if (Sid)
+		HeapFree(RfGetProcessHeap(), HEAP_ZERO_MEMORY, Sid);
+
+	if (hAdvapi)
+		FreeLibrary(hAdvapi);
+
+	if (DisposeProcessHandle)
+	{
+		if (hToken)
+			CloseHandle(hToken);
+	}
+
+	return (bFlag ? pSid : NULL);
+}