diff --git a/dlls/shlwapi/shlwapi.spec b/dlls/shlwapi/shlwapi.spec
index deb8a48..40e2ee9 100644
--- a/dlls/shlwapi/shlwapi.spec
+++ b/dlls/shlwapi/shlwapi.spec
@@ -804,6 +804,8 @@
 @ stdcall StrStrNW(wstr wstr long)
 @ stdcall StrStrNIW(wstr wstr long)
 @ stdcall StrStrW(wstr wstr)
+@ stdcall StrToInt64ExA(str long ptr)
+@ stdcall StrToInt64ExW(wstr long ptr)
 @ stdcall StrToIntA(str)
 @ stdcall StrToIntExA(str long ptr)
 @ stdcall StrToIntExW(wstr long ptr)
diff --git a/dlls/shlwapi/string.c b/dlls/shlwapi/string.c
index 903c981..f2d3812 100644
--- a/dlls/shlwapi/string.c
+++ b/dlls/shlwapi/string.c
@@ -91,7 +91,7 @@ static void FillNumberFmt(NUMBERFMTW *fmt, LPWSTR decimal_buffer, int decimal_bu
  * Format an integer according to the current locale
  *
  * RETURNS
- *  The number of bytes written on success or 0 on failure
+ *  The number of characters written on success or 0 on failure
  */
 static int FormatInt(LONGLONG qdwValue, LPWSTR pszBuf, int cchBuf)
 {
@@ -124,7 +124,7 @@ static int FormatInt(LONGLONG qdwValue, LPWSTR pszBuf, int cchBuf)
  * after the decimal point
  *
  * RETURNS
- *  The number of bytes written on success or 0 on failure
+ *  The number of characters written on success or 0 on failure
  */
 static int FormatDouble(double value, int decimals, LPWSTR pszBuf, int cchBuf)
 {
@@ -855,8 +855,34 @@ int WINAPI StrToIntW(LPCWSTR lpszStr)
  */
 BOOL WINAPI StrToIntExA(LPCSTR lpszStr, DWORD dwFlags, LPINT lpiRet)
 {
+  LARGE_INTEGER li;
+  BOOL bRes;
+
+  TRACE("(%s,%08X,%p)\n", debugstr_a(lpszStr), dwFlags, lpiRet);
+
+  // Test on lpszStr is done into StrToInt64ExA
+  if (!lpiRet)
+  {
+    WARN("Invalid lpiRet would crash under Win32!\n");
+    return FALSE;
+  }
+
+  bRes = StrToInt64ExA(lpszStr, dwFlags, &li.QuadPart);
+  if (bRes)
+    *lpiRet = li.u.LowPart;
+
+  return bRes;
+}
+
+/*************************************************************************
+ * StrToInt64ExA	[SHLWAPI.@]
+ *
+ * See StrToIntExA.
+ */
+BOOL WINAPI StrToInt64ExA(LPCSTR lpszStr, DWORD dwFlags, LONGLONG *lpiRet)
+{
   BOOL bNegative = FALSE;
-  int iRet = 0;
+  LONGLONG iRet = 0;
 
   TRACE("(%s,%08X,%p)\n", debugstr_a(lpszStr), dwFlags, lpiRet);
 
@@ -922,8 +948,34 @@ BOOL WINAPI StrToIntExA(LPCSTR lpszStr, DWORD dwFlags, LPINT lpiRet)
  */
 BOOL WINAPI StrToIntExW(LPCWSTR lpszStr, DWORD dwFlags, LPINT lpiRet)
 {
+  LARGE_INTEGER li;
+  BOOL bRes;
+
+  TRACE("(%s,%08X,%p)\n", debugstr_w(lpszStr), dwFlags, lpiRet);
+
+  // Test on lpszStr is done into StrToInt64ExW
+  if (!lpiRet)
+  {
+    WARN("Invalid lpiRet would crash under Win32!\n");
+    return FALSE;
+  }
+
+  bRes = StrToInt64ExW(lpszStr, dwFlags, &li.QuadPart);
+  if (bRes)
+    *lpiRet = li.u.LowPart;
+
+  return bRes;
+}
+
+/*************************************************************************
+ * StrToInt64ExW	[SHLWAPI.@]
+ *
+ * See StrToIntExA.
+ */
+BOOL WINAPI StrToInt64ExW(LPCWSTR lpszStr, DWORD dwFlags, LONGLONG *lpiRet)
+{
   BOOL bNegative = FALSE;
-  int iRet = 0;
+  LONGLONG iRet = 0;
 
   TRACE("(%s,%08X,%p)\n", debugstr_w(lpszStr), dwFlags, lpiRet);