Tag Engine Error

[Peter_Heseltine]

After recently adding a new virtual channel in Max I received the following error from the tag engine.
"The group National Instruments.DaqOPC configured on the server National Instruments.DaqOPC could not be set to the active state: Your OPC server is likely non-compliant with the OPC specification with respect to the following function IOPCGroupStateMgt::SetState()"

Please see attached screenshot for actaul full message.

Does anyone know how to correct this problem please?

[SachaE]

Hi,
apologies for the delay in responding.
There's a few options but I'm wondering if you could investigate the following url troubleshooting
:
http://www.ni.com/support/labview/dsc/daq_tr7.htm

also how many virtual channels do you have?

What version of Traditional DAQ are you using?
What's the hardware?
What version of LabVIEW and LabVIEW DSC are you using?
What's the operating system?

Depending on the names you're using and the harware, you may be running into the following specific situation :

If you're using both a Data Aquisition Board, and SCXI, the OPC Server only looks at the beginning of a channel string when it's determining how to group channels. So it sees "Dev " and "Dev1_SCXI_MOD3" both as "Dev1" and puts them in the same group and passes this to NI-DAQ. NI-DAQ gets those channels and say AO Config returns an error because you can't have two different channels from two different devices configured in the same channel list. The DAQ error does not get passed back through the OPC layer, so it just looks like an OPC error. The best workaround would be to use a separate, inexpensive device to control the SCXI chassis and use the MIO outputs on their own.

Thanks

Sacha Emery
National Instruments (UK)

[bdougr]

check to make sure the hardware channel is not used in another tag.
only one tag can use a channel - even if the tag is not used in DSC.

[Peter_Heseltine]

Thanks for taking the trouble to reply.
I actually found the reason for this error several months ago.
As with so many things the actual reason for this error was a bit obtuse.
The opc server was coonected to both high speed Digital I/O and a relative low speed voltage/temperature logger.
I found that I needed to split the tags belonging to the lower speed acquisition from the high speed tags.
I did this by assigning different groups and setting different update rates.
It took me many hours to figure this myself with a few well intentioned, genuinely helpful but untimately fruitless calls to NI.