Lost Attributes on copy

[jc508]

Hi,
I am having trouble with file attributes being lost on copy / sync.
We are using NTFS extended attributes to store information we are interested in.
For some extra analysis I am replicating the data to my home computer. The process involves syncing files from a source machine to a USB drive, then from the USB to a drive on the target machine.
All drives are NTFS format and FreeFileSync has had no trouble copying this data for ages, including all the attributes.
Up until recently all the components were Windows 10. Now a couple of the nodes are Windows 11.

Today I did an extra step and synced the file set to a folder on another disk ready for tests.
A massive number of files have lost some or all of their attributes.

Given how well FreeFileSync has performed for years I dont expect it has suddenly caught an illness.
I do suspect Windows 11 is sick though - I have caught it before where File Manager lies about attributes.
It will show one set of attributes for a file, click some other file and then back to the first one and the attributes will have changed.
What I would like to know is
a) How does FreeFileSync actually do a copy? Does it use the same underlying functions that FileManager will use ?
b) Have any other users noticed this behaviour - especially on Windows 11

Thanks for any input
JC

[jc508]

For example, these symptoms are similar to an allegedly solved windows bug ....

..you might have intermittent issues saving, or copying, or attaching files using 32-bit apps which are large address aware and using the CopyFile API. Windows devices are more likely to be affected by this issue when using some commercial/enterprise security software which uses extended file attributes. We are not receiving reports that copying files using File Explorer is affected, but CopyFile API used within apps might be affected.

Does FFS use 'CopyFileAPI' ?

[jc508]

I ended up re-building my PC (and going back to Win 10) and the above problems have gone away. I have also independently run the same tests on another Win 11 machine and the issues are not present. So I can only conclude it was some deep gremlin in only my computer.
Just for the record
JC

[xCSxXenon]

Thank you for reporting back! Glad it ended up resolved for you