diff --git "a/dll/win32/mshtml/navigate.c" "b/dll/win32/mshtml/navigate.c"
index a7b28eb2af0..bd54662bccd 100644
--- "a/dll/win32/mshtml/navigate.c"
+++ "b/dll/win32/mshtml/navigate.c"
@@ -957,6 +957,36 @@ static void on_stop_nsrequest(nsChannelBSC *This, HRESULT result)
     }
 }
 
+#ifdef __REACTOS__
+HRESULT map_nsresult(nsresult nsres)
+{
+    switch(nsres) {
+    case NS_OK:
+        return S_OK;
+    case NS_ERROR_OUT_OF_MEMORY:
+        return E_OUTOFMEMORY;
+    case NS_ERROR_NOT_IMPLEMENTED:
+        return E_NOTIMPL;
+    case NS_NOINTERFACE:
+        return E_NOINTERFACE;
+    case NS_ERROR_INVALID_POINTER:
+        return E_POINTER;
+    case NS_ERROR_INVALID_ARG:
+        return E_INVALIDARG;
+    case NS_ERROR_UNEXPECTED:
+        return E_UNEXPECTED;
+    /* Only defined in Wine */
+//    case NS_ERROR_DOM_NO_MODIFICATION_ALLOWED_ERR:
+//        return 0x80700007; /* according to tests */
+//    case NS_ERROR_DOM_SYNTAX_ERR:
+//        return E_INVALIDARG; /* FIXME: Throw SyntaxError for IE9+ modes */
+    case NS_BINDING_ABORTED:
+        return E_ABORT;
+    }
+    return E_FAIL;
+}
+#endif
+
 static HRESULT read_stream_data(nsChannelBSC *This, IStream *stream)
 {
     DWORD read;
@@ -1041,8 +1071,12 @@ static HRESULT read_stream_data(nsChannelBSC *This, IStream *stream)
                 (nsIRequest*)&This->nschannel->nsIHttpChannel_iface, This->nscontext,
                 &This->nsstream->nsIInputStream_iface, This->bsc.readed-This->nsstream->buf_size,
                 This->nsstream->buf_size);
-        if(NS_FAILED(nsres))
-            ERR("OnDataAvailable failed: %08x\n", nsres);
+#ifdef __REACTOS__
+        if(NS_FAILED(nsres)) {
+            WARN("OnDataAvailable failed: %08lx\n", nsres);
+            return map_nsresult(nsres);
+        }
+#endif
 
         if(This->nsstream->buf_size == sizeof(This->nsstream->buf)) {
             ERR("buffer is full\n");