Poor handling of large TIFs and ZIPs

I have an ongoing problem using DOpus with some large files.
I utilise a lot of large (over 1 Gb) zip, tiff and psb (photoshop) files.
Quite often when I want to perform a simple operation such as rename or cut-paste DOpus will return an error saying the file is being used by another process.
I then have to close DOpus, kill it in task manager, open Windows Explorer and run the process (instantaneously) in Explorer. If I don't kill DOpus Explorer returns an error saying file is being used by DOpus.
Sometime simple moving of files within a drive also takes ages as if I was transferring between drives.
What background processes are going on here to cause simple processes to hang and how can I stop them?

That could be a lot of things, inside or outside of Opus. We aren't aware of anything that would cause that in Opus 12.14, but we've seen things do it in the past. (The ones we've seen within Opus itself have all been dealt with, but it could be a shell extension or antivirus doing it, perhaps.)

Which version of Opus are you seeing that with?

Have you tried the FAQ about this type of issue? Crash, exit or high CPU when viewing certain directories

It happened with Opus 10 and again with 11. It happens at home and also on Portable at work on a very different machine config. Different AV, different files, different OS. Happens on Win 7 and Win 10. It seems to me that it's trying to generate thumbnails or something that restricts other processes. Also happens on delete very often that deleting a file sets off a progress bar that takes 10s of minutes to finish.

If you delete something in a large zip file, and Preferences / Zip & Other Archives / Zip Files / Use temporary file when copying to Zip files (safer but slower) is turned on, then the whole zip file gets re-written, which can take some time (but usually nowhere near 10s of minutes, even with large files, unless we're talking about extremely slow media or network drives here). If antivirus scans the new zip file at the same time, it'll be slower.

There isn't enough detail here for me to say very much, though; all I can do is make guesses about why things might be slow, most of which would already in the FAQs (the one linked above, and also General slowdown or instability investigation steps ).

If there are specific steps that trigger an issue, with a known file, I can try to reproduce that. Or if you want to send us some Process Monitor logs, I can look at those ( Process Monitor instructions ).

Knowing whether or not Opus 12 is affected could also be useful, in case whatever the issue is has already been fixed, but I'm happy to look at logs and try things if details are given.

I'll have a look at Process monitor when I get a chance. It's definitely an internal Opus issue though since if I try to delete a file with windows explorer an error message pops up saying the file is being used in Opus but if I kill Opus the process will work instantly.

That doesn't necessarily mean much as if antivirus decides to scan the file when Opus tries to access it, or if a shell extension holds on to it, then it's going to be done inside the dopus.exe process the same as if our code was doing it.

It might mean it's our code, but it isn't conclusive either.