(Error code -36)

I am trying to copy files across to my external hard drive.

When doing so I get this error message:

The Finder can’t complete the operation because some data in “File name” can’t be read or written.

(Error code -36)

I tried it with an avi file first of all, it will get to around 170mb transferred and this error will appear. I then tried a photograph and it copied across fine. I tried another video file and again it got to around 170mb and the error appeared. I then tried another image file and a video file and both will not begin the transfer and bring up the same error message straight away.

I am then unable to view the files on the external hard drive and have to force eject.