Hoping someone can shed some light on a problem which I've been pursuing through Support, so far without luck. I set a weekly scheduled differental backup of my entire PC (all partitions selected) to external HDD, followed by validation. The backup runs OK, but during the validation the E00070003 error occurs. If I then manually validate the backup, this usually works fine without complaint. If I set an immediate backup & validate, this too usually works. I've several times set Windows checking both internal & external HDDs on its slowest/most thorough scan settings. Several hours later, no bad sectors are ever reported. I've restored data from the backups, likewise without error. Ive deleted and then recreated the Acronis backup location. I've freed up lots of space on both source and target HDDs, in case that was the problem. The fact that this error only surfaces during the weekly scheduled backup has made it very slow to pursue through Support. I've sent log files, and installed/reinstalled SnapAPI drivers, but without success. I'm using the latest build of ATI v11. It would appear that the backup does indeed run OK, but that something within the following validation makes Acronis think that it hasn't worked. This is a strange problem, and I'm rather tired of getting up on a Saturday morning to find the same error message every week. So any wisdom would be appreciated.