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Bad quality (3); Reading from OPC server (20); Unknown reason

Using OPCClient object to communicate with RSLinx Single Node OPC server in Lookout 5.1.  Have a problem where I'll get the error  "Bad quality (3); Reading from OPC server (20); Unknown reason (00000000) continuously in my alarms window that almost immediately clears itself then comes up again.  Every time it is a different item that pops up.  Most of the time rebooting the computer will clear the problem.  Any ideas?
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Are you using XP SP3?

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No, XP SP2.


Think the problem might be with communications to my plc, possibly a hardware issue.  Found the following error in RSLinx :  "When loading this topic, it was not possible to resolve the target path that is part of the topic's configuration."



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From the alarm message, it is more like a communication error or wrong configuration in OPC Server. The connection between OPClient object and the RSLinx has been established, but the value returned from RSLinx has bad quality. You can first try the OPC client test software from Rockwell and make sure the RSLinx is working well.


When you create the OPClient object in Lookout, select "In-Process Server" and "Flat".

Ryan Shi
National Instruments
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