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Seemingly random COMException

02 Jan 2018 20:58 #5786 by support

in DCOMCNFG on the server side, under Console Root -> Component Services -> Computers -> My Computer -> DCOM Config, in Properties for the your server, under the Identity tab, what does it say? The interactive user, The launching user, "This user" (and a data for a specific user account), or The system account (services only)?


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02 Jan 2018 20:20 #5785 by jgreg311
I've been battling with DCOM configuration and permissions, and I thought I had it all figured out, but I'm still getting (what seems to be random) COMExceptions when reading an item's value (via EasyDAClient.ReadItem):

Exception Type: OpcLabs.EasyOpc.OperationModel.OpcException
Exception Message: An OPC operation failure with error code -2147467238 (0x8000401A) occurred, originating from 'OpcLabs.EasyOpcRaw.DataAccess.RawEasyDAClient'. The inner exception contains details about the problem.
Inner Exception Type: System.Runtime.InteropServices.COMException
Inner Exception Message: The server process could not be started because the configured identity is incorrect. Check the username and password.

I imagine it has to be related to DCOM permissions, but I don't understand why it seems to work for hours, and then it stops working all of a sudden. It will start working again, at some point.
I left it working over the entire weekend, and it did this several times throughout the time period.

Setup: running as a Windows service connected to an RSLinx Remote OPC Server. The Windows process is configured to run as a local user with the same name and password as an admin user setup on the OPC server (I couldn't get it to work at all until I did this).

Any help or ideas of where to look would be GREATLY appreciated. We've purchased licenses and are very happy so far, I just wish DCOM wasn't such a pain.


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