updated for version 7.4.506
Problem:    MS-Windows: Cannot open a file with 259 characters.
Solution:   Fix off-by-one error. (Ken Takata)
diff --git a/src/os_mswin.c b/src/os_mswin.c
index 0dfd7d6..b50b86c 100644
--- a/src/os_mswin.c
+++ b/src/os_mswin.c
@@ -411,7 +411,7 @@
 	     * - convert the result from UCS2 to 'encoding'.
 	     */
 	    wname = enc_to_utf16(fname, NULL);
-	    if (wname != NULL && _wfullpath(wbuf, wname, MAX_PATH - 1) != NULL)
+	    if (wname != NULL && _wfullpath(wbuf, wname, MAX_PATH) != NULL)
 	    {
 		cname = utf16_to_enc((short_u *)wbuf, NULL);
 		if (cname != NULL)
diff --git a/src/version.c b/src/version.c
index 178a784..deaa7b5 100644
--- a/src/version.c
+++ b/src/version.c
@@ -742,6 +742,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    506,
+/**/
     505,
 /**/
     504,