Default retry count is 1 million and default wait is 30 seconds. I recommend reducing that to a realistic level (i.e. 2 retries and 5 or 10 seconds for the wait). If you're trying to mirror drives, this might be simpler than excluding files and directories.
Copy the data over.<br />
robocopy <source> <target> /MIR /R:2 /W:3
Refresh file security for all files, without copying any file data.<br />
robocopy <source> <target> /E /COPY:S /IS /IT /R:2 /W:3
Replicate data (/MIR) and security (/SEC) for changed files, and update just the security (/SECFIX) for unchanged files.<br />
robocopy <source> <target> /MIR /SEC /SECFIX /R:2 /W:3
If these are file shares you are migrating to a new drive, follow these additional steps.
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\LanmanServer\Shares