Robocopy syntax is markedly different from its predecessors (copy and xcopy), in that it accepts only folder names, without trailing backslash, as its source and destination arguments.
Robocopy outputs to the screen, or optionally to a log file, the names of all the directories it encounters, in alphabetical order.
"Failed" can mean that there was an I/O error that prevented a file being copied, or that access was denied.
Robocopy's "inter-packet gap" (IPG) option allows some control over the network bandwidth used in a session.
In theory, the following formula expresses the delay (D, in milliseconds) required to simulate a desired bandwidth (BD, in kilobits per second), over a network link with an available bandwidth of BA kbps: In practice however, some experimentation is usually required to find a suitable delay, due to factors such as the nature and volume of other traffic on the network.
The methodology employed by the IPG option may not offer the same level of control provided by some other bandwidth throttling technologies, such as BITS (which is used by Windows Update and BranchCache).
It was developed by Derk Benisch, a systems engineer with the MSN Search group at Microsoft, and required .NET Framework 2.0.