Copy in background sometimes does not copy file date/time

[BeckYang]

TC version: v9.0a 32bit
Platform: Windows 7 64bit

The situation does not happened everytime, so I cannot offer the precise steps to reproduce it.
The typical steps that I do:
1. Select menu item: "Mark" -> "Mark Newer, Hide Same Files"
2. Several files are selected.(My observe: file size is not matter. It also happenes when no file is overwrited...)
3. Press F5 and "F2 Queue" to copy in background.
4. Do something like moving cursor, changing folder...

After the background copy dialog closed, select menu item: "Mark" -> "Mark Newer, Hide Same Files" again.
Some files are selected due to differnt date/time. The date/time of copyed files are current time.

Is there any other people get similar situation?

[ghisler(Author)]

Which copy method do you use? The default method in Configuration - Options - Copy/Delete (where most of that page is disabled) uses a Windows function (CopyFileEx) which copies both the file and its timestamp, so this works for most users. However, I know that even CopyFileEx fails to copy the timestamp with certain virus scanners in the background.

[BeckYang]

My setting of Copy/Delete is default method.
Look like this is CopyFileEx API issue of Windows.

So far, most of case happened when I backup files to external USB hard disk.
Can I prevent the situation by change setting?
For example: Change setting to experts mode, put checked to "Use compatiblility mode for following drivers" and "USB sticks".

[ghisler(Author)]

You can try other methods, where TC itself copies the time stamp, but it will probably not work either - normally CopyFileEx is the most compatible method. You need to find out what background program is interfering with CopyFileEx (e.g. virus scanner, firewall etc).