I have tried repeatedly to create a disk image using both Acronis True Image Home 2009 and Macrium Reflect and both fail when validating the image.

The image is sent to my external Seagate FreeAgent Pro via a USB connection and runs OK until the validation stage. The software people say it is a hardware problem. I have carried out long tests of the new FreeAgent Pro using SeaTools and they tell me it is OK so what next?
Any ideas appreciated.
I am almost at the point of giving up on imaging and just back up the data files to the FreeAgent but that means it will take longer to rebuild from a catastrophic failure.
Tom