diff --git a/fhem/docs/fhem.html b/fhem/docs/fhem.html
index 64d74f393..f9b3e456a 100644
--- a/fhem/docs/fhem.html
+++ b/fhem/docs/fhem.html
@@ -118,7 +118,9 @@ description and <a href="faq.html">faq.html</a> for the F.A.Q.
      <li>Windows driver installation:
           <a href="http://fhz4linux.info/tiki-index.php?page=Driver%20installation">
           http://fhz4linux.info/tiki-index.php?page=Driver%20installation</a> <br>
-          (best:use "Solution B")    At this time, we only support virtual com port on windows</li>
+          (best:use "Solution B";change only the value PID to the FDTI default. Your supplied software will not harm.)<br>
+	  At this time, we only support virtual com port on windows. Only COM1..COM9 are known to work
+	  ->COM10 will result in a "unknown Device" error.</li>
     <li>Instructions for Nas/Routers (NSLU2):
           <a href="http://www.martin-haas.de/fhz/nslu2fhz">
         http://www.martin-haas.de/fhz/nslu2fhz</a></li>