TL;DR: do backup software replicate the EFS encryption on destination?
D:\Documents\ (from a 1 TB hard drive's main folder, NTFS)
I:\BackupDocuments\ (on a 1 TB external USB hard drive, NTFS)
xxcopy "D:\Documents\" "I:\BackupDocuments\" /clone /ff-3602 /jj0 /pz0 /pb
Problem: only ~ 1 every 10 encrypted subfolders are encrypted in the destination (visible in green in the Windows Explorer).
Also, let's say the
D:\Documents\Test\ fully-encrypted folder contains 500 files. Then only a few (randomly chosen among the 500!) files are encrypted in the destination
I:\BackupDocuments\Test. That's really strange.
Note: I also tried with another backuping software (SyncBack), and it seems to be the same problem.
Question: Is that a general problem when backuping a drive containing certain encrypted folders, that the encryption is not always replicated on destination (sometimes true, sometimes false, randomly)?
Edit: I've done additional tests:
Copying directly with Windows Explorer (Copy/Paste) result in keeping encryption on destination
I did a new test with destination disk initially empty, then
xxcopywill not replicate encryption at all to destination
I did a new test with destination disk initially empty, then SyncBack (backup software) will replicate encryption to destination for all files
I did a test with destination = exact backup of source, except that encryption is on on all source files, and encryption is off on all destination files. Then running a SyncBack backup will cause overwrite of the destination to have encryption on (that's good!) for most files (.MP3, etc.), but not all files (.URL files are untouched, left unencrypted on destination).