*should read "said", not "sayd" obviously. apparently I can't edit posts once they are up.
Please open Resource Monitor, switch to the Disk tab, expand everything and take a screenshot. What does it look like?
Got most of it in the capture (see attached).
Thanks again for all of your time - and Happy Holidays to you and yours 
Many thanks!
That looks perfectly normal to me, so scratch that idea.
Does setting Preferences / Miscellaneous / Advanced: no_external_change_notify = False make a difference? You would not want to leave it that way, but if it improves performance then it might be something we can fix.
No, no difference. And to make matters worse, I'm on my laptop right now and the same issue IS present on the laptop - and to a greater extent than the desktop. Dopus has crashed a couple of times already and I've only been logged on for an hour. I'm going to uninstall and reinstall shortly.
no such folder exists - sorry
Did dopus.exe actually crash, or just freeze up or something else? If it crashes, there should be a crash dump in most cases.
Froze and was accompanied by system message (program failed to respond - wait for program to respond or end task) - happened several times - each time I had to "end task". I refer to that as a crash, but I recognize we don't all use the same terminology for various system events. Anyway, I uninstalled and reinstalled but there appear to be some issues with the laptop today (from out of nowhere - also a new computer - about 6 months old - never had any previous problems). I'm going to use Acronis to restore to a previous date and go from there. Really more concerned with the desktop at this point, though the fact that the same problem did occur on more than one system raises some questions I guess.
Ah ok, that isn't a "crash".
At this point I am out of ideas, I'm afraid, short of removing all background processes (WinPatrol, KAV, Acronis, PerfectDisk were all doing a fair amount of stuff in the background. Acronis's shell extension has been known to cause all kinds of trouble, too. But nothing pointed to any of them in particular in the logs.)
Keep in mind that one of the troubleshooting steps I took was disabling all shell extensions. Anyway, I get it. It's an anomaly. Again, I appreciate all your time and assistance. I'll keep trying various thing and if anything works I'll post back. Similarly, should you think of anything else please post in this thread (I'm subscribed).
Thanks much Leo.
Hi. I´m just curious of some thing: does explorer work well?
yes it does.
I take it back lead. While Windows Explorer doesn't have exactly the same problems as Dopus, I just noticed that when I click on E: drive in the file pane it populates very slowly. I then played around in explorer and sure enough, navigation is spotty - just as it is in Dopus. Any thoughts as to what would cause this issue across both file managers?
NOTE: I've tried a couple of other 3rd party file managers (xplorer2, etc) and they work VERY quickly and very well without any of the issues described above.
I don't think there are any more ideas. All the ones we had for Opus would be a superset of those which would apply to Explorer as well.
I'd look for similarities between the two machines affected. If they both have some software or a driver in common, try uninstalling them to see if it makes a difference, and use things for a while to make sure it doesn't just seem to have gone away, since it appears to be intermittent at times.
Several definitive statements in this thread have turned out to be incorrect after using things for a bit longer, so it may be that they also show problems, just in different situations or only after using them more extensively. Either way, it's probably not relevant. There is some interaction between software or drivers, or possibly a hardware or configuration problem on the machine, and it's affecting both Opus and Explorer at least. Knowing what it doesn't affect probably won't help to solve it.
Since the issue affects Explorer, a general Windows help forum may have ideas which we haven't thought of. If I think of anything else, I'll add it here as well, but having thought about it on & off over the holiday, I can't think of anything new to suggest.
Understood and thanks again. The fact that I'm on staff at several Windows forums will help me reach the right people 
Leo - Dopus slowed down to a point where it was unusable. I didn't want to have to do without it, so I set aside some time and went through the process of a selective startup. It appears that Windows Search is the culprit - at least on the desktop system. I haven't had a chance to get to my laptop yet.
I will post an update as soon as I've had a chance to disable Windows Search on the laptop and "live with" both systems for a few days to insure that is indeed the cure.
I can confirm that disabling the Windows Search service has returned normal functionality to Dopus on both the desktop and laptop.
Leo, thank you again for all of your time and effort.
Any idea what was triggering Windows Search to do things?
Are there stored queries under File Collections / Stored Queries? (coll://Stored Queries) Maybe they were being refreshed and the queries were such that they caused a lot of disk or CPU use.
It could also be a bug in the indexing service, or one of the plugins (which can involve 3rd party components for indexing different file types). Certain XML files used to cause it to go into an endless loop until Microsoft patched it.
Actually Windows Search wasn't "doing" anything. One of the first things I do on any new system is disable indexing (both drive by drive in "properties" and in Control Panel). I had the indexing service set to Manual on one system and Auto (Delayed Start) - which is the default - on the other and it appeared that it was stuck on "loading" without actually starting - so yes - it may be a bug in the service. And again, there was no high cpu or disc usage that I could identify.
Anyway, thought I'd post the results so you could have it on file in the event that anyone else runs into a similar situation. At the very least, disabling the service is a valid troubleshooting step. As soon as I clicked on DISABLE and made certain the service was stopped on the laptop, Dopus began working normally. Didn't even require a reboot.
Be well and best wishes for a great 2016 and beyond!!