ATI 2010 Operation Failed Message

I have two SSD's installed on my system under Windows 7 plus one external HD via usb.

Disk 0 has two Primary partitions, C: and D:
Disk 1 has three primaries, F: T: and S:

I have used Acronis True Image 2010 and earlier versions for years to create backup images (tib files) of C: and D: from Disk 0 to the external drive. Never had any problems other than those created by me.

I just had the need to back up the S: partition for the first time. I got a message saying 'The Operation Failed'. I tried to do the same with the other two partitions with the same error. I seems ATI doesn't like to create a tib file from Disk 1.

I then booted to the ATI CD and tried again. The operation appeared to complete. The tib file was created but when I tried to restore from it ATI said the file was corrupt.

I then replaced the Disk 1 SSD with the old spinner and and the same thing happened.

In summary, ATI will do its job correctly from Disk 0 but fails when it tries to backup a partition on Disk 1.

Can someone help me?

Thank you.