opc servers dcom error

[Militant_Daos]

Hello all.

This problem may look stupid, but, as far as I know by this time no one provided any clear way to solve it.

The essence of the problem is that I cannot establish communication between NI OPC Servers and any client

application or data communication framework (Quick OPC Client, DataSocket etc.)

When I try to enumerate OPC items I always get this error: "Error -2147024891 occurred at GetOPCServerList.vi 
Possible reason(s): LabVIEW: (Hex 0x80070005) Access denied."

I have already tried to configure DCOM security as it is described in OPC Foundation manual: http://www.opcfoundation.org/DownloadFile.aspx?RI=326 and Automated Solutions' one: http://www.automatedsolutions.com/technotes/opcserverconnectivity/Default.asp

I have performed these steps on three PCs (1 running Win7 x64 SP1; two other -- WinXP x32 SP3). Firewalls (both system firewall and third-party) are off.

All required services are running. So, what I'm doing wrong?!

All suggestions are highly appreciated.

[Larry_H]

Hello,

I have a couple preliminary questions for you:

1. What version of NI OPC Servers are you installing?

2. What version of LabVIEW and the Datalogging and Supervisory Control (DSC) Module are you installing?

3. When you try this across 3 different machines, are the installations from the same source? Example, are you using the same CD to install the software? Or maybe the same .exe file?

In the meantime, I did some searching of our database and found the following KnowledgeBase article regarding the behavior you're seeing: Why Do I Get Error -2147024891 When Trying to Connect to My OPC Server?

if you find that you do have the service, listed in the article, installed, I would suggest uninstalling that service and reinstalling the components from the link provided in the article.

Regards,

[Militant_Daos]

Hello!

1) I use NI OPC Servers v. 4.500.462.0

2) LabVIEW's version is 2010 SP1; DSC Module's version is also 2010 SP1.

3) I installed the software from the same DVD on each of those three machines.

Also I have tried to uninstall and re-install OPC DA components; this didn't help.

Best regards.

[Larry_H]

Hello,

I did some more research and found a couple of sources/solutions for us to explore. It appears that there have been a number of users who have experienced this problem but the solution for each case has varied.

1. A customer has seen this behavior in the past and the assisting engineer discovered that the problem was with the installation of the NI OPC Server, and DSC Module. Being that you're seeing this behavior across 3 computers with the same source of installation, I'd like to try a different installation source. Since you are using DSC 2010 SP1, I located a download link for you: http://ftp.ni.com/evaluation/labview/ekit/other/downloader/2010sp1LvDSC_downloader.exe I checked the version of NI OPC Servers that you are using and I believe that is the same as NI OPC Servers 2010. If so, please uninstall the version of NI OPC Servers you have on one of your computers and try installing the evaluation from here: https://lumen.ni.com/nicif/us/evalopc/content.xhtml. Please be sure to uninstall the DSC Module and OPC Servers from one of your computers before you reinstall them from the links I've provided you.

2. Manually registering opcproxy.dll according to this document: http://digital.ni.com/public.nsf/allkb/E9887094890516EB862570A700486F0E?OpenDocument helped another customer who was experiencing this same behavior.

3. In another instance, re-registering the opcenum service via the command line, as shown by this document: http://digital.ni.com/public.nsf/allkb/E19CAE2BEF4F3780862570D900663A9F?OpenDocument solved this same issue for another customer.

4. Please be sure to take step 1 before you following the other proposed solutions.

Regards,

[Al_Niz]

Hi,

Links are down