Recently, I was given a new pc at work. My old work pc Opus 8 was working fine. When I clicked on windows explorer Opus came up instead which is what I wanted. With this new pc I installed Opus and and have the setting under preferences/misc/explorer replacement set to "Replace explorer for all folders" selected. Now when I click on windows explorer it opens as window explorer instead of opus. If I click on the Opus icon in the system tray it then opens a separate opus window. What am i doing wrong. I am using Opus8 version 8.2.2.5 U.
Try turning off Explorer replacement, OKing the Preferences dialog, then open Preferences again and turn Explorer replacement back on again. That should make Opus re-write the required registry settings.
Nope, it did not work the same thing is happening.
When you say you're clicking on Windows Explorer, do you mean the icon that actually says "Explorer" (that will always run Explorer), or do you just mean you're double-clicking some folders to open them?
When I click on Windows Explorer in the Quick Launch. When I right click on the Start button and click Explore. When click on the Start button and click Windows Explorer. Unless I am losing it but I recall on my older work pc when i clicked on the Windows Explorer from the Quick launch toolbar Opus opened up for me. That's what I am trying to accomplish on this newer pc.
Well then if you haven't "lost it", you certainly seem to have "misplaced it temporarily" 
. The 'Explorer Replacement' mode in Opus causes system calls that ask Windows to 'open' a folder to open the folder in Opus instead of Explorer... Clicking on an actual shortcut to explorer.exe is telling Windows to specifically run Explorer, and that is not something Opus will 'intercept'.
If all you're talking about are these shortcuts, then just get used to clicking on an Opus shortcut instead... or replace the Explorer shortcuts with Opus shortcuts and change their names and icons to Windows Explorer .