I want Dopus to have no more than one window open, ever. I have the recommended settings modified: lauching Dopus from double-clicking the desktop and the taskbar icon are disabled because I don't use those methods, and I have checked "Open external folders in a new tab". The latter setting isn't enough because I'm using a virtual desktop manager to hide windows and I'm using the taskbar to open windows. What happens is I switch desktops with VirtuaWin, Dopus gets moved (hidden) to another desktop, and then when I want Dopus back I click the icon in the taskbar, which runs dopus.exe. With some applications, such as FreeCommander, this opens the existing window instead of starting a new instance or window. With Directory Opus, however, a new lister is opened every time the application is launched.
Running dopus.exe on its own, with no other arguments on the command-line, and when Opus is already running, will always open a new window.
If VirtuaWin can change what it runs when it launches Opus then you could add arguments to the command line which make it show the existing window instead. I don't know if VirtuaWin allows that, though; that's a question for VirtuaWin's forum.
If you want VirtuaWin to show Opus on all desktops then it can definitely do that.
What arguments for dopus.exe can I use?
Using DOpusRT.exe is best, rather than DOpus.exe
That can run any Opus commands via /cmd as well as a bunch of other things.
This might do what you want:
"C:\Program Files\GPSoftware\Directory Opus\DopusRT.exe" /acmd Go NEW LASTACTIVELISTER
DOpusRT.exe docs are here: