Copy files *without* taking ownership

Turns out Robocopy can do this incredibly easily. Simply include the /B option on your command line, to copy files in Backup mode. This requires that you run as Administrator.

My command line:

robocopy /MIR /B "E:\Documents and Settings" "C:\DeadDriveBackup\Documents and Settings"

The given answer did not work for me; this did.

Robocopy has a /COPY argument used to specify which parts of files to copy. Available to copy are data, attributes, timestamps, security information (NTFS ACLs), ownership information, and auditing information. If you're looking to copy everything in one directory to another perfectly, use this:

robocopy /E /B /COPYALL "C:\One" "C:\Two"

Let's analyse:

• /E copies all files, including empty directories. This works like /MIR, but doesn't delete anything in the destination.
• /B copies in "backup mode", giving Robocopy the permission to overwrite ACLs (file permissions).
• /COPYALL is an alias to /COPY:DATSOU, which copies all file data, including file ownership and permission (ACL) data.

Are you copying a user profile?

I was, and there are some extra caveats. Default Windows user profiles contain directory junction loops, and Robocopy cannot be configured to create new junctions rather than following them. The above Robocopy command will fail and create difficult-to-remove directory trees, so use this command which will exclude junctions.

robocopy /E /B /COPYALL /XJ "C:\One" "C:\Two"

For compatibility you should probably recreate the default directory junctions in a user profile:

mklink /J "Application Data" "AppData\Roaming"
mklink /J "Cookies" "AppData\Local\Microsoft\Windows\INetCookies"
mklink /J "Local Settings" "AppData\Local"
mklink /J "My Documents" "Documents"
mklink /J "NetHood" "AppData\Roaming\Microsoft\Windows\Network Shortcuts"
mklink /J "PrintHood" "AppData\Roaming\Microsoft\Windows\Printer Shortcuts"
mklink /J "Recent" "AppData\Roaming\Microsoft\Windows\Recent"
mklink /J "SendTo" "AppData\Roaming\Microsoft\Windows\SendTo"
mklink /J "Start Menu" "AppData\Roaming\Microsoft\Windows\Start Menu"
mklink /J "Templates" "AppData\Roaming\Microsoft\Windows\Templates"
attrib /L +S +H +I "Application Data"
attrib /L +S +H +I "Cookies"
attrib /L +S +H +I "Local Settings"
attrib /L +S +H +I "My Documents"
attrib /L +S +H +I "NetHood"
attrib /L +S +H +I "PrintHood"
attrib /L +S +H +I "Recent"
attrib /L +S +H +I "SendTo"
attrib /L +S +H +I "Start Menu"
attrib /L +S +H +I "Templates"