Hello I found the reason: i installed active Perl version 5.10.1.1007 MSWIN32-x64. Now it work! regard Marcel -- View this message in context: http://mrtg-mailinglists.795376.n2.nabble.com/MRTG-in-64-bit-windows-server-2008-tp1097401p5107590.html Sent from the MRTG Users Mailinglist mailing list archive at Nabble.com.