Error when Copying/Pasteing AVCHD Files (Error code -36)

[Dave Mercer]

Having major problems copying files from one external HDD to another. Folder starts copying over then stops and gives the message: "The Finder can’t complete the operation because some data in “AVCHD” can’t be read or written.
(Error code -36)"

Basically I copied the folder from my Canon C100's SDHC card to an external HDD (file structure intact), but now I can't copy that folder (and contents) to another backup HDD. I get the Error Code -36. Permissions seem to be okay.

This is the first time I've had this problem in 1 1/2 years using the camera / Laptop / HDD combination.

Any ideas?
Thanks!