I/O Error when reaching a disk image

[ChrisJ]

Hi,

I have regularly been using SD for a couple months now. When I did my Smart Backup this week, I got the following error message and so an unsuccessful backup:

| 11:00:52 PM | Info | WARNING: Caught I/O exception(5): Input/output error
| 11:00:52 PM | Info | WARNING: Source: /Users/chris/Movies/NAF Choice Forum.dmg, lstat(): 0
| 11:00:52 PM | Info | WARNING: Target: /Volumes/Backup Chris Jerdonek/Users/chris/Movies/NAF Choice Forum.dmg, lstat(): 0
| 11:00:52 PM | Info | Attempting to copy file using copyfile().
| 11:05:21 PM | Info | Attempting to copy file using ditto.
| 11:09:44 PM | Error | ditto: /Users/chris/Movies/./NAF Choice Forum.dmg: Input/output error

What is the cause/way to fix this? The above file (a copy of an unprotected DVD) was new since my last backup.

Also, after a failed backup like the above, what is the status of my backup drive -- is it no longer bootable and/or only partially correct?

Thanks,
Chris