You are here: NI Home > Support > Product Reference > Manuals > LabVIEW 8.6 Datalogging and Supervisory Control Module Help

Complete the following steps to troubleshoot OPC I/O servers.

1. Configure the DCOM security settings on both the client and server. The OPC Client I/O servers connect to both local and remote OPC servers through DCOM. Refer to the Using OPC via DCOM with Microsoft Windows XP Service Pack 2 manual for information about configuring DCOM security settings.
2. Configure the security settings on both the client and server.
   1. In the Windows Control Panel, navigate to the Administrative Tools folder.
   2. Double-click the Local Security Policy shortcut to launch the Local Security Settings utility.
   3. In the Security Settings tree, select Local Policies»Security Options. Ensure the value of Network access: Sharing and security model for local accounts policy is Classic - local users authenticate as themselves.
3. Configure the service username for the Shared Variable Engine (SVE). OPC Client I/O servers connect to OPC servers by using the SVE. The username of SVE is SYSTEM by default.

   Note  If you use the default SVE username, you must configure local OPC servers to work with OPC Client I/O servers. Otherwise, you must ensure the username of SVE is an administrator.

   1. In the Windows Control Panel, navigate to the Administrative Tools folder.
   2. Double-click the Services shortcut to launch the Services utility.
   3. In the Services window, right-click the National Instruments Variable Engine service and select Properties from the short menu. The National Instruments Variable Engine Properties dialog box displays.
   4. Click the Log On tab to display the Log On page.
   5. Select the This account option.
   6. Enter an administrator username and password in the text boxes.
   7. Click the OK button to close this dialog box.
   8. Restart the SVE to apply the configurations.

My Profile | Privacy | Legal | Contact NI   © 2009 National Instruments Corporation. All rights reserved.   |