Free file-copying utility TeraCopy speeds up file transfers and can pause, resume and test file copy operations. With TeraCopy you can:
Copy files faster. TeraCopy uses dynamically adjusted buffers to reduce seek times. Asynchronous copy speeds up file transfer between two physical hard drives.
Pause and resume file transfers. Pause copy process at any time to free up system resources and continue with a single click.
Error recovery. In case of copy error, TeraCopy will try several times and in the worse case just skips the file, not terminating the entire transfer.
You can also use TeraCopy to diff the contents of two directories by running a "Test" copy, which shows you which files exist in the destination directory as compared to the source. If you've ever had Windows fail at the very last minute of a multi-gigabyte file copy, TeraCopy's for you. TeraCopy is a free download for home use for Windows.