Hi Richard,
The error you are getting when opening the Tag Details Query template is because the PI server does not have Groups, and the LIST GROUPS directive is not valid in PCo for a PI Source. This query is executed from the TagQuery template object in MII, which uses the older LISA protocol to communcate with PCo (and the obsolete UDS before that). MII Versions 12.2 and later have a new PCoQuery tempate which, among other things, does not execute the LIST GROUPS directive when the Tag brower window in the Query template is opened. The error per se does not cause any issues with subsequent tag queries from MII to PI.
In the PCo log you should see a LIST TAGS RECURSIVELY WHERE ROWCOUNT = XXX; message from MII, followed by a response when PCo returns the results to MII. Do you see any additional messages that occur between the request and the response that would indicate why the query is taking 2 minutes to execute?
Also, what is the exact version of PCo 2.3 that you are using? What are the settings for the PI source Agent?
Regards, Steve
