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>From: Unidata Support <address@hidden> >Organization: Unidata Program Center/UCAR >Keywords: 200208141327.g7EDR9K06634 McIDAS-X v2002 Hi Martha, We reviewed our FTP and TCPD log files and saw numerous refusals for connection by your machine, wx1sleet.west.tasc.edu/147.81.139.58. The problem is that forward lookup for this machine fails: % nslookup wx1sleet.west.tasc.com Server: laraine.unidata.ucar.edu Address: 128.117.140.62 *** laraine.unidata.ucar.edu can't find wx1sleet.west.tasc.com: Non-existent host/domain even though reverse name lookup succeeds: % nslookup 147.81.139.58 Server: laraine.unidata.ucar.edu Address: 128.117.140.62 Name: wx1sleet.west.tasc.com Address: 147.81.139.58 Since we enforce both forward and reverse name lookup before allowing any FTP connection, your machine was refused. We also contacted the name servers in your domain and see that they will not do both forward and reverse name lookup for wx1sleet. It is possible that there has been some changes in your network setup recently to fight known DNS security holes. If I were you, I would check with your network folks to find out exactly what is going on. Tom