I was having some issues copying video files from my iPhone via USB, and discovered some very strange behavior that seems to be caused by Directory Opus. Not only did Directory Opus seem unable to copy all the files to the local drive itself, but strangely it seems that somehow, simply opening the folder on the iPhone with Directory Opus messes up Windows' ability to copy the files altogether.
I'll post a screencap of some various testing I did with timestamps to explain what's going on at each part. Also during the recording I had open Nirsoft's "Inside Clipboard" tool which might give some clues.
The video was pretty big so I just put it on Google Drive:
0:00 - Navigating to iphone folder in both DO and Explorer
0:16 - Copying to clipboard with DO
0:23 - Pasting with DO -- Only 3 of the files end up copied
0:32 - Copying to clipboard with DO again
0:35 - Pasting again with DO - None seem to copy over (On my screen I actually saw a quick flicker of the temporary files of DO showing, but it didn't show up in the video)
0:44 - Copying to clipboard in DO and pasting into Explorer - It first appears it copied, but the files are wrong - notice the file sizes. All the files it DID copy WERE actually files on the iPhone, but they are not the ones added to the clipboard, it's like it copied the wrong files but used the names from the clipboard files. The 756 KB files are all actually the same image file copied 3 times. The 37MB files are 3 copies of the same video, etc. The 1KB file is actually some kind of metadata file iPhone makes for screenshots I guess.
1:05 - Copying to clipboard via Explorer and also pasting to folder via Explorer - Shows some error
1:22 - Trying to copy again and paste again with explorer - It copies different files this time
1:38 - I clear the clipboard
1:44 - Copying to clipboard and pasting via Explorer again - Error again
1:59 - I disconnected and re-connect the iPhone, then navigate to the videos with explorer
2:20 - I copy the files and also paste with explorer - The files copied correctly
2:55 - I do the same thing again and it copies them correctly again
3:44 - Copy the files to clipboard with DO
3:55 - Paste the files with DO - Temporary files show but it doesn't copy them
4:05 - Again try copying the files to clipboard and pasting with DO - Only 3 of the files are copied, but they are the correct files
4:20 - Copy and paste files with explorer - It copies the wrong files
4:38 - Close DO window then copy and paste again with explorer - It apparently copies them BUT the names are mixed up
5:11 - Delete the files and paste again with explorer - Again copies but names are jumbled again
Another thing I tried but didn't record, was that I disconnected and reconnected the iphone without DO open to reset everything, and again it would copy and paste fine with explorer. Then I only opened the folder on the iPhone with DO (but didn't copy anything). I noticed DO was reading metadata from files I guess, showing in the address bar, spinning thing, and when I tried to copy and paste the files with explorer while it was doing that, explorer showed an error that said "The requested resource is in use".
I could be totally wrong but it seems like DO might be somehow affecting some kind of cache or index Windows might use to keep track of files on USB devices? I don't actually know how Windows works in that regard so I have no idea if there is such a cache, but it's the only thing I could think of that might explain how DO would affect Explorer's ability to copy stuff.