Thanks to this post on StackOverflow, I learned a new trick with diagnosing TNS Names issues. First, you need to download this tool called Process Monitor from SysInternals.
Installing the program is pretty easy. Simply unzip the program and place it in a good location such as the Program Files directory:
I always like to create a shortcut in the Start Menu. If you right click on the Programs menu in your Start Menu, you can choose the open option to open it. Then, drag with your right mouse button, and you can drop a shortcut in your start menu:
Once you have Process Monitor installed, you can use the filter to narrow it down to show where it is looking for tnsnames. Here is what I found that works:
Add the process name for the process that you want to check. Use psdmt for Data Mover. pside for App Designer. PrcsAppSrv for the App Server launched by psadmin.
Then, if you put tnsnames in for the Path it will show where it is looking for the tnsnames file.
This tool works great for all kinds of situations. I have also used it to diagnose other connection issues. I found it was loading the wrong Oracle client on one installation. I found it was looking in the registry in the wrong place for Tuxedo settings because I had the wrong version.
So, this is a great tool that will help with troubleshooting.
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