Have you tested similar copies with other software to see if they're similarly effected?
What does Task Manager show for the CPU and Storage utilisation after the copy completes?
Could you generate some process snapshots while the problem is happening? We can use those to see which code is active at that time. (Assuming there's high CPU or Storage usage, and it's attributed to dopus.exe.)
Possibilities include:
- If Opus has folder tabs open displaying the files (not just the parent directories), it may be inspecting them to get metadata. Close any unnecessary folder tabs to see if it helps.
- Antivirus and/or search indexing scanning all the new files.
- Hardware/drivers being slow when dealing with a backlog. (Make sure you have installed the motherboard's SATA drivers, for example. They can be very important.)
- Shell extensions etc. could be reacting to the changes as well (although usually only if they can see the files in an open folder, so this is closely related to the first possibility; they may just exacerbate the issue.)
FWIW, over the last 3 days I've been moving a huge amount of data from HDD to SSD, including file copies using Opus where over 2 million files and 3TB of data were moved in a single batch, and I haven't seen similar issues.