diff --git a/dlls/msvcr100/msvcr100.spec b/dlls/msvcr100/msvcr100.spec
index 2f14f591273..e56913feaeb 100644
--- a/dlls/msvcr100/msvcr100.spec
+++ b/dlls/msvcr100/msvcr100.spec
@@ -1116,7 +1116,7 @@
 @ cdecl _mbsicoll(str str)
 @ cdecl _mbsicoll_l(str str ptr)
 @ cdecl _mbsinc(str)
-@ stub _mbsinc_l
+@ cdecl _mbsinc_l(str ptr)
 @ cdecl _mbslen(str)
 @ cdecl _mbslen_l(str ptr)
 @ cdecl _mbslwr(str)
diff --git a/dlls/msvcr110/msvcr110.spec b/dlls/msvcr110/msvcr110.spec
index 29918fd3b06..f64c6cf30b5 100644
--- a/dlls/msvcr110/msvcr110.spec
+++ b/dlls/msvcr110/msvcr110.spec
@@ -1473,7 +1473,7 @@
 @ cdecl _mbsicoll(str str)
 @ cdecl _mbsicoll_l(str str ptr)
 @ cdecl _mbsinc(str)
-@ stub _mbsinc_l
+@ cdecl _mbsinc_l(str ptr)
 @ cdecl _mbslen(str)
 @ cdecl _mbslen_l(str ptr)
 @ cdecl _mbslwr(str)
diff --git a/dlls/msvcr120/msvcr120.spec b/dlls/msvcr120/msvcr120.spec
index 286c1a7e616..8e6a169a187 100644
--- a/dlls/msvcr120/msvcr120.spec
+++ b/dlls/msvcr120/msvcr120.spec
@@ -1484,7 +1484,7 @@
 @ cdecl _mbsicoll(str str)
 @ cdecl _mbsicoll_l(str str ptr)
 @ cdecl _mbsinc(str)
-@ stub _mbsinc_l
+@ cdecl _mbsinc_l(str ptr)
 @ cdecl _mbslen(str)
 @ cdecl _mbslen_l(str ptr)
 @ cdecl _mbslwr(str)
diff --git a/dlls/msvcr80/msvcr80.spec b/dlls/msvcr80/msvcr80.spec
index 4d113a504a5..4bef365a7c8 100644
--- a/dlls/msvcr80/msvcr80.spec
+++ b/dlls/msvcr80/msvcr80.spec
@@ -788,7 +788,7 @@
 @ cdecl _mbsicoll(str str)
 @ cdecl _mbsicoll_l(str str ptr)
 @ cdecl _mbsinc(str)
-@ stub _mbsinc_l
+@ cdecl _mbsinc_l(str ptr)
 @ cdecl _mbslen(str)
 @ cdecl _mbslen_l(str ptr)
 @ cdecl _mbslwr(str)
diff --git a/dlls/msvcr90/msvcr90.spec b/dlls/msvcr90/msvcr90.spec
index 32e05f38946..19f9335f545 100644
--- a/dlls/msvcr90/msvcr90.spec
+++ b/dlls/msvcr90/msvcr90.spec
@@ -766,7 +766,7 @@
 @ cdecl _mbsicoll(str str)
 @ cdecl _mbsicoll_l(str str ptr)
 @ cdecl _mbsinc(str)
-@ stub _mbsinc_l
+@ cdecl _mbsinc_l(str ptr)
 @ cdecl _mbslen(str)
 @ cdecl _mbslen_l(str ptr)
 @ cdecl _mbslwr(str)
diff --git a/dlls/msvcrt/mbcs.c b/dlls/msvcrt/mbcs.c
index 6363086b129..e8194a690ad 100644
--- a/dlls/msvcrt/mbcs.c
+++ b/dlls/msvcrt/mbcs.c
@@ -654,12 +654,20 @@ size_t CDECL _mbclen(const unsigned char* str)
     return _mbclen_l(str, NULL);
 }
 
+/*********************************************************************
+ *		_mbsinc_l(MSVCRT.@)
+ */
+unsigned char* CDECL _mbsinc_l(const unsigned char* str, _locale_t locale)
+{
+    return (unsigned char *)(str + _mbclen_l(str, locale));
+}
+
 /*********************************************************************
  *		_mbsinc(MSVCRT.@)
  */
 unsigned char* CDECL _mbsinc(const unsigned char* str)
 {
-  return (unsigned char *)(str + _mbclen(str));
+    return _mbsinc_l(str, NULL);
 }
 
 /*********************************************************************
diff --git a/dlls/msvcrt/msvcrt.spec b/dlls/msvcrt/msvcrt.spec
index e18308848a3..5ed054df51f 100644
--- a/dlls/msvcrt/msvcrt.spec
+++ b/dlls/msvcrt/msvcrt.spec
@@ -737,7 +737,7 @@
 @ cdecl _mbsicoll(str str)
 @ cdecl _mbsicoll_l(str str ptr)
 @ cdecl _mbsinc(str)
-# stub _mbsinc_l(str ptr)
+@ cdecl _mbsinc_l(str ptr)
 @ cdecl _mbslen(str)
 @ cdecl _mbslen_l(str ptr)
 @ cdecl _mbslwr(str)
diff --git a/dlls/ucrtbase/ucrtbase.spec b/dlls/ucrtbase/ucrtbase.spec
index 1026aa48de7..e40a4ccaea5 100644
--- a/dlls/ucrtbase/ucrtbase.spec
+++ b/dlls/ucrtbase/ucrtbase.spec
@@ -631,7 +631,7 @@
 @ cdecl _mbsicoll(str str)
 @ cdecl _mbsicoll_l(str str ptr)
 @ cdecl _mbsinc(str)
-@ stub _mbsinc_l
+@ cdecl _mbsinc_l(str ptr)
 @ cdecl _mbslen(str)
 @ cdecl _mbslen_l(str ptr)
 @ cdecl _mbslwr(str)
@@ -1200,7 +1200,7 @@
 @ cdecl _o__mbsicoll(str str) _mbsicoll
 @ cdecl _o__mbsicoll_l(str str ptr) _mbsicoll_l
 @ cdecl _o__mbsinc(str) _mbsinc
-@ stub _o__mbsinc_l
+@ cdecl _o__mbsinc_l(str ptr) _mbsinc_l
 @ cdecl _o__mbslen(str) _mbslen
 @ cdecl _o__mbslen_l(str ptr) _mbslen_l
 @ cdecl _o__mbslwr(str) _mbslwr