Acronis TIH 11 Failed to prepare data stream

Hi Experts,
 I am using Acronis True Image Home 2011 latest build
 I keep receiving the below error on scheduled tasks, sometimes the backup runs fine and others the result is as below. However the destination is accessible.
 I have configured it on various machines and only happen on 1 or 2.

I have re-created the backup, selected various locations, attempted HDD and Secure zone. As Acronis instruct I turned off the consolidation and still nothing.
 
I have been unable to find any further information anywhere else.

1 Information 11/2/2011 11:00:01 PM Operation My partitions backup started.
 2 Information 11/2/2011 11:00:02 PM Analyzing partition '0-0'...
 3 Information 11/2/2011 11:00:02 PM Analyzing partition '1-1'...
 4 Information 11/2/2011 11:00:02 PM Analyzing partition 'C:'...
 5 Information 11/2/2011 11:00:03 PM Analyzing partition '1-3'...
 6 Information 11/2/2011 11:00:03 PM Analyzing partition 'F:'...
 7 Error 11/2/2011 11:00:04 PM Failed to prepare data stream. Check whether the source and target partitions exist.
 10 Error 11/2/2011 11:00:04 PM Operation has completed with errors.

Look forward to reading your comments.