Some time ago I moved a large folder containing SQL server files from my laptop to an Iomega external 160 GB USB HDD to free space on the laptop. It went without problems. The folder consists a number of subfolders, each of which contains a .mdf file, a .ldf file, and a text file. The former two are usually 2 to 20 GB.
Recently I decided to replace this HDD with a larger, 2 TB Hitachi one. I wanted to move the SQL files from the Iomega to the Hitachi. However Windows keeps bringing up the error "Error copying file or folder: Cannot copy (filename): There is not enough free disk space." It offers to use disk cleanup, and if I try that I get offered some files to delete with 0 KB in each one. Completing this action has no effect - if I try to move the files again it repeats the result.
Some folders have been transferred complete with their large files, but the ones that have transferred are all 4 GB or less.
The Hitachi is presently 143 GB used, 1.67 TB free. The Iomega is presently 124 GB used, 36 GB free
Why is this happening, and how can I complete the transfer?