Use of NetDDE requires the proper settings of DDE Share on all nodes with which Advantech WebAccess/SCADA will be interfacing. NetDDE relies on Windows Security. The logged on Windows User on the Client must be recognized user by the Net DDE Server computer (i.e. must be a user on both machines with the same user name and password). For a first time developing a NetDDE application, it is recommended to log on with the same user name and password on both the NetDDE Server PC and the Client.
Note- NetDDE is not reliable and frequently will not reconnect after a computer reboot or other error. NetDDE is particularly difficult to connect in Windows XP.