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OPC AddItems Failed for tag

Question asked by MELang on Jul 10, 2015
Latest reply on Mar 2, 2017 by cramsey

I'm having an issue involving the OPC DA interface for which I'm hoping someone can provide some insight.  I have a 120 delay built into the interface at startup.  However, when the interface loads its tags after the 120 seconds, a few tags generate the following error:

 

AddItems failed for tag xxxxxxx, type VT_BSTR: The ItemID is not syntactically valid (c0040008)

 

My understanding of the OPC server, and OPC in general, if very limited.  But I have been told that these are "dynamic" tags on the OPC server and may not exist when the interface attempts to load the tag.  If I restart the interface, I do not get the errors.  Therefore, I believe the ItemID to be correct.

 

I thought there might be an option which might cause the interface to periodically attempt to reload tags which generated errors at interface startup.  However, I have not found such an option.

Can anyone provide some insight and/or guidance into my issue?

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