Why does file copy halt for long period at 100% before completing process, it might copy 1GB file in 4 seconds to 100% and then wait for 15 seconds before final finish?
Can something be done?
Using latest version but this "problem" has been there from very start of using Dopus 11 and on two different laptops that runs under win 7/64
It could be one of two things:
It isn't really halting, but the destination device or filesystem is using a huge write buffer which means a lot of data is written into the buffer (in memory) very quickly, but you then have to wait at the end for it to make its way on to disk. (Unlike some copy tools, Opus will not close the progress dialog until the data is flushed to the disk.)
Or:
When the file is closed, your antivirus scanner starts taking a look at it and will not allow the final close/flush requests to complete until it has finished scanning it. This is likely if the issue happens with large .exe or archive files but does not happen with, say, a large video file.
(There are some other possibilities but they're a lot less likely and would involve a NAS doing something weird when asked to set file attributes or other metadata, for example.)
It "halts" even when copying files inside SSD-raid which is quite fast
I will try if "MS security essentials" have something do with this problem, just kill it before copy process and see if "halt" shortens or is affected in any way
copied 1.42GB file over USB3.0 into external HDD, 100% took 37sec, final finish 1min42sec
that just is not normal
and ms-security was killed before this test run
Try disabling write caching for the drive and then see what results you get in Explorer.
Write cache is allways disabled, never use it with SSD drives.
Copied 1,19GB folder with 5 files, Dopus did it in 59 sec, explorer in 10 sec.
Open Task Manager and go to the Performance tab, then select the drive that is being written to.
Repeat the tests there and see when the data really stops being written to the drive. It will sometimes be a long time after the progress dialog indicates completion and closes.
Also, if you're copying in Opus and then in Explorer, try doing it the other way around. (Or vice versa.)
If there is still a large time difference in the real disk activity then something very strange is happening with the device. There are some settings in Opus that may be worth trying, but let's see if the above tests show things are still different first.
You may also want to check the source drive in Task Manager, to see if it is doing a lot of work before the copy begins. If so, that could explain things. (e.g. If Opus is configured to extract data from the files, and that takes a long time with those files for some reason, then it may slow down the drive.)
Which file types are involved in your test?
If using WIN764 enterprice "performance monitor" for disc frites/access to monitor copy process, it shows that copying is doing something at the background after 99% for very looooooong time, explorer is faster but by minutes. Anyway, I don't use copy over 500MB files, they take just ages to finish, instead I use move, it finishes seconds and is not so prone to errors or broken files.
Forgot to test the same copy-halt on other laptop but it is in pieces at the moment.
That shows the filesystem is doing a lot of buffering.
You could enable non-buffered I/O via Preferences / Miscellaneous / Advanced. Set the copy_nonbufferio_threshold value there to 1 MB and see if it makes the progress bar seem more representative. It may also speed things up.
(Note that it can cause problems with some badly made USB sticks which weren't tested with the non-buffered modes of the Windows APIs. It's rare but does affect some people.)
I am not sure what you mean about Copy vs Move as, unless source and destination are on the same partition, they are exactly the same operation just with a deletion at the end. Move means "rename if possible, otherwise copy-then-delete". The same is true in Explorer and all file managers. Choose the operation by whether you want to copy or move the data, not anything else.
Moving files happens between inner SSD-drive and outer USB3 HDD-hub 4 meters away so it does not involve rename but copy-delete.
I might try your hints, which SSD drives should I "nonbuffer" in name of science, SATA3 2,5" RAID-1 with 2x SSD mSata 500GB 850EVO or SATA 2,5" SSD 500GB 840EVO - 500GB 850PR0 - 1TB 850EVO
SSD RAID-1 is fastest, faster than same config at RAID-0
I might jump completely on apples macbook (got iphone and ipod already) soon so it is sad to leave Dopus but in other hand get computer that works allways everytime every day untill end of time 
It isn't a per-drive setting. Just make the change I mentioned in my previous post and see if it improves things.
In the name of science non-buffered copy process crawled 50MBs and made things even slower, no joy.
It is just weird that moving 5GB file takes 10 seconds and copying 2 minutes easy.
Just tested that does copy or move direction make any difference, it did not or the difference was quite small.
If I skip SSD drives and try testing copy and move solely on old enviroment with old regular 3,5" SATA3 HDD's, one using USB3.0 dock and one using eSATA.
What do you think, any other ways that should be tested?
I don't know, to be honest.
Opus just reports what is happening. If there is a delay when the file is flushed to disk or closed, it's happening because of something, but I can only guess. It could be the hardware or filesystem or drivers buffering data more than you might expect, or it could be antivirus scanning the file when it is closed, or maybe something I haven't thought of. Those are the main two causes, though.