The OPC Client uses various methods for browsing local and remote machines for OPC servers.
Browsing OPC Servers on the Local Machine
When browsing for OPC servers on the local machine, three methods can be used:
- OPCEnum.exe - this is a tool provided by the OPC Foundation that helps clients browse local or remote machines. The OPC Client installs this utility on your local machine as part of the product installation.
- Browse the Windows Registry for OPC servers.
- By CategoryID - any OPC 1.0 and 2.0 server that is registered with the Windows StdComponentCategoriesMgr as an OPC 1.0 or OPC 2.0 CATID Server displays with this method. This method is not supported for use with remote machines.
Browsing OPC Servers on a Remote Machine
When browsing for OPC servers on a remote machine, two methods can be used:
- OPCEnum.exe - this is a tool provided by the OPC Foundation that helps clients browse local or remote machines. The OPC Client installs this utility on your local machine as part of the product installation.
- Browse the Windows Registry for OPC servers. You must have Administrator rights to be able to do this on a remote machine.
All servers that are found using any of the above methods are displayed in this list.
Browse Failure
If no servers were found on the machine, the message "No servers were found on the machine" displays. You must then verify that either the correct machine name/TCP/IP address was entered in the previous page or that the OPC server(s) are correctly installed on the given machine.
If one or more methods fail, a message box displays indicating the methods used and which ones succeeded or failed. It also displays an error message indicating the reason for failure, as returned by the system. Any server(s) found are listed. You can select a server from the list or remedy the reason for the failure and rerun the search.
One possible remedy includes modifying your DCOM settings, even if your OPC server is running locally. For information about modifying your DCOM settings, refer to How do I Set up Security for using the I/O Server Remotely.
IMPORTANT: If you are browsing OPC servers on a local or remote machine, then OPCENUM must reside and be registered on that machine for browsing to work correctly. While most OPC server applications install and register this file, some may not. You can download this file from www.opcfoundation.org. Currently, it is contained within the OPC Core Components 2.00 Redistributable 2.30.msi file. After you download the file, run the .msi program and follow the instructions on screen to install it. You must do this on each of the local or remote machines you intend to browse.
