Version 12.6 x64
Yes, it continues to appear after cleaning and installing a fresh system. Funny, right click errors do not occur with Microsoft's Explorer.
Am I interested in searching through Registry keys to find the culprit? No way! Those days have passed years ago.
You don't like criticism just like I don't like buying software that has had an error for several years with no correction.
Do the errors stop if you turn on the Preferences / Miscellaneous / Windows Integration / Hide Windows items on file context menus option mentioned as a quick fix in the FAQ about this issue?
If they do, then the errors are not caused by Opus but by something else installed on your system. The rest of the FAQ explains how to track down what is causing it, and it's not something we can do for you unless you give us remote access to your computer.
We can help track things down in some cases if you send us a crash dump. If the problem is in Opus, that will usually let us locate it. If the problem is in a 3rd party shell extension, that will usually let us tell you which one is causing the problem. Details for that are also in the FAQ.