Error "access denied" when I browse to an OPC

[METO]

The following is generated in ICONICS OPC DataSpy when I browse to an OPC
Item in my National Instruments.OPCLabVIEW server on a remote 2000 PC.

ICONICS OPC DataSpy ready (free version)
Creating Instance of "National Instruments.OPCLabVIEW" on node Nak-mis...OK
(0x00000000, The operation completed successfully.)
Calling IOPCBrowseServerAddressSpace::QueryOrganization()...FAILED
(0x80070005, Access is denied.)
Calling IOPCBrowseServerAddressSpace::ChangeBrowsePosition()...FAILED
(0x80070005, Access is denied.)
Calling IOPCBrowseServerAddressSpace::BrowseOPCItemIDs()...FAILED
(0x80070005, Access is denied.)


I am able to browse to my tag items using NI's Server Explorer and I can
succeffully run NI example c
lients.

I would like to be able to verify OPC connectivity independent of an NI
solution as we will be expected to serve data to another vendors client.

thank you very much.

chris

[Roli]

Chris,

currently, I do not have the setup to verify this behavior. However, for me it looks like your DCOM registration is not correctly configured.

Remote OPC is going through the DCOM configuration/settings/access rights of your networked PCs. To enable access rights you should have a correct domain server that has correctly set up users. With the Start>Run>dcomcnfg you can specify the access rights for all the ActiveX/OPC servers on your computer.

1. Start>Run>dcomcnfg

1. Go to Applications tab and choose Properties of LabVIEW Datalogging and Supervisory Control Module

1. Go to Security tab and verify if all the three permission catagories are correctly set for the user who tries to remotly access/launch/configure the OPC server.i>

If you use default settings you have to make sure the default is correctly configured as well. To verify go back to Distributed COM Configuration Properties window and go to the Default Security tab.

To start of with the basic test, I would try to be logged in to the two computers with the same user account.

In addition, I recommend to read this Knowledgebase article - you might already have done that...
Accessing a Remote OPC Server Using the LabVIEW DSC Module
Remote OPC Server Communication on Windows NT/2000/XP [broken link removed]

Hope this helps
Roland

PS: For general information about DCOM/OPC you might find more info :
www.opcfoundation.org : E.g. This pretty white-paper:
OPC DCOM White Paper
www.microsoft.com : E.g. This detailed: COM Security Frequently Asked Questions

[METO]

Roli

Thank you.

I have just returned from a vacation and will go through our set-up again.

chris