Error Code 59: An unexpected networkerror occurred. [backupWrite]

[Johnnyc42]

I currently try to synchronize between two Samba shares on two EMC VNX 3150 NAS system. I keep getting every two or three minutes I get this message "Error Code 59: An unexpected network error occurred. [BackupWrite]"

Both NAS device a have two 10GB aggregated links with default MTU.

Could you the recommend FreeFilesync settings for samba share.

[Zenju]

The source file is "sparse", right? FFS falls back to BackupWrite in this case because Windows cannot copy sparse files with CopyFileEx. FFS only does so if the target file system supports this, but I bet your NAS cannot actually handle sparse files, but incorrectly advertises support.