I am getting this error both on a Network Drive AND seeing it on a USB connected drive.
On the Network Drive, the command I am using is....
ROBOCOPY C:\Users\GH\Documents\ "\\SDS115J\home\GH Folder"\GHDTandDocs\%RunDate%\GHDocsBkuP\ /MIR /NDL /NFL /R:0 /TEE.... and all works well apart from 3 Folders failing "Access is Denied" on the Time-Stamping process.
These folders are : My Music, My Pictures & My Videos - yet these folders are "seemingly" NOT in my Documents folder.... clearly some sort of problem due to them being Windows Folders (they are under my User name, without the "My" Prefix).
Error Message Screenshot to follow (when Account verified by TechNet).