# Connecting to Kepware OPC Server

**URL:** <https://forum.inductiveautomation.com/t/connecting-to-kepware-opc-server/1315>\
**Category:** Archived Topics\
**Created:** [October 5, 2009, 10:26pm UTC](https://forum.inductiveautomation.com/t/connecting-to-kepware-opc-server/1315 "2009-10-05T22:26:46Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Step7](https://avatars.discourse-cdn.com/v4/letter/s/45deac/32.png) [@Step7](https://forum.inductiveautomation.com/u/Step7)\
**Post date:** [October 5, 2009, 10:26pm UTC](https://forum.inductiveautomation.com/t/connecting-to-kepware-opc-server/1315/1 "2009-10-05T22:26:46Z")

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I can’t seem to browse my Kepware OPC Server (“Cannot connect to OPC Server for browse”). The servoce settings look ok, and “test connections” passes. In the log, I get the following error:

[quote]Unable to cast COM object of type ‘System.\_\_ComObject’ to interface type ‘OpcRcw.Comn.IOPCServerList2’. This operation failed because the QueryInterface call on the COM component for the interface with IID ‘{9DD0B56C-AD9E-43EE-8305-487F3188BF7A}’ failed due to the following error: No such interface supported (Exception from HRESULT: 0x80004002 (E\_NOINTERFACE)).  
at OpcCom.ServerEnumerator.CLSIDFromProgID(String progID, String host, ConnectData connectData)  
at FactorySQL.OPCServerManager.GetServerInfoForServer(String ServerID)  
at FactorySQL.OPCServerPool.AddNewConnection(String ServerName, String Owner, Boolean AllowFailure)[/quote]

What should I try now?

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**Author:** ![Colby.Clegg](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/colby.clegg/32/3282_2.png) [@Colby.Clegg](https://forum.inductiveautomation.com/u/Colby.Clegg)\
**Post date:** [October 6, 2009, 12:06am UTC](https://forum.inductiveautomation.com/t/connecting-to-kepware-opc-server/1315/2 "2009-10-06T00:06:01Z")

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It looks like it’s not even making it to kepware- this error appears to be coming from OPCEnum, which is a service that provides information about the opc servers on a machine.

It’s possible that your opc installation is a bit “mis-aligned”. Did you recently install a new server? At any rate, you could try the following:

1. Stop your opc servers, re-run the Inductive Automation installer, but choose “Custom” and only select “OPC Core Components” from the other software.

-OR-

1. Re-install Kepware. Their installer usually does a good job of making sure the core components are OK.

Hope this helps,

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<div class="post-metadata">

**Author:** ![Step7](https://avatars.discourse-cdn.com/v4/letter/s/45deac/32.png) [@Step7](https://forum.inductiveautomation.com/u/Step7)\
**Post date:** [October 6, 2009, 12:20am UTC](https://forum.inductiveautomation.com/t/connecting-to-kepware-opc-server/1315/3 "2009-10-06T00:20:19Z")

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Yeah, that’s probably it. I’ve never used FactorySQL on this machine, and I’m not even sure of the order of installation. I’ll do a fresh install of Kepware tomorrow, which I’ll need to do eventually anyway. Thanks.