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Entry type: FAQ Entry ID: 24360824, Entry date: 01/05/2007

What are the special features of the changed startup behavior of the OPC data access server with SIMATIC NET CD Edition 2006?

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Configuration note:
When OPC groups are activated, the OPC DA server loaded with SIMATIC NET PC software CD Edition 2006 is initially only able to return "OPC_QUALITY_WAITING_FOR_INITIAL_DATA=0x20" for items with VT_EMPTY-type data values.

Please ensure that your OPC client supports this return value. Otherwise, your OPC client application needs to be changed accordingly.

This return value is a valid value according to the OPC specification. 

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