Well, those registry entries simply turn on DCOM logging, which can sometimes give you more info as to exactly why access is being denied. The messages appear in the windows event viewer, so check that out and see if there’s anything there.
Here’s a quick rundown of DCOM settings that you might check. First start by opening dcom config… Start->Run->dcomcnfg , expand Component Services, Computers, and then right-click “My Computer” and select properties.
- On “Default Properties” tab, make sure Default Authentication Level=None, Default Impersonation Level=Identify.
- On COM security, there are 4 buttons. Check that on all 4 “everyone” and “anonymous user” and “SYSTEM” have at least local rights. For troubleshooting you should add remote rights as well, because even on the local machine the communication can appear to be remote sometimes.
- Close that screen. Expand “My Computer” under dcom config. Select the “DCOM config” folder. Find OPCEnum, right click, select “Properties”. I should explain something quickly: most opc servers use the default settings you just set in 1 & 2, but OPCEnum usually sets its own, which is why I’m having you check this.
General Tab: authentication level should be none.
Location: Only “run app on this computer” checked.
Security: usually all 3 will be custom. Click “edit” and make sure that the same accounts mentioned in #2 have access for everything.
Endpoints tab: no change
Identity: Set to “the system account”.
And that should be it. After doing all that, it’s probably best to restart windows. Also, make sure that the firewall is off, or at least TCP port 135 is open.
Regards,