diff --git a/dlls/mshtml/nsembed.c b/dlls/mshtml/nsembed.c
index 5593c6b1f8e..109b6ad77f3 100644
--- a/dlls/mshtml/nsembed.c
+++ b/dlls/mshtml/nsembed.c
@@ -1100,8 +1100,8 @@ BOOL is_gecko_path(const char *path)
     WCHAR *buf, *ptr;
     BOOL ret;
 
-    buf = heap_strdupAtoW(path);
-    if(strlenW(buf) < gecko_path_len)
+    buf = heap_strdupUtoW(path);
+    if(!buf || strlenW(buf) < gecko_path_len)
         return FALSE;
 
     buf[gecko_path_len] = 0;