I am reading this thread because I have the same Acronis TI problem - my backup operation succeeded but when I read the log it indicates some errors, and I get the "corrupted image" message. I used to have the same difficulties with Norton Ghost 2003 and had to run chkdsk c: /f /r to get a good backup file. Furthermore, I usually had to run chkdsk TWICE. After running the first time look at the event log (COntrol Panel -> Administrative Tools -> Event Viewer -> Application) under winlogon. You will see the chkdsk log which probably indicates "minor inconsistencies" numbering 30-40 or more if you have not run chkdsk recently. I keep running chkdsk until the minor inconsistencies are less than 10, then I do the backup operation. This archive validates, though I have to admit that I have never fired the RESTORE guns in anger.
I am now in the process of running chkdsk the second time for a TI backup and I will report back.
-DAC