Get "Acronis Loader Fatal Error" message

I am running Windows XP (Home Edition) SP3, on a 250GB (IDE) HDD (Western Digital).

I have used the WD edition of TrueImage "Clone Disk" many times before, to backup my system without any problems.

I recently purchased a new 500GB (IDE) HDD (Hitachi), and tried to copy my 250 GB HDD to the new drive using Acronis TrueImage 2013 "Clone Disk" tool.

Selecting Source and Destination drives etc. appeared to proceed OK until the reboot stage.

Instead of starting normally, the computer now "hangs" with the following message:
Starting Acronis Loader...

...and a few seconds later:
Acronis Loader Fatal Error: Boot Drive (Partition) Not Found.
Press to try to boot your OS...

When I hit the key, the computer starts up as normal. But the new HDD is still blank.

Is there any way I can get rid of the error message, so I can at least start my computer normally?