TrueImageCmd /deploy returns error "Failed to lock partition 1-1"

Hi,

I am using the TrueImageCmd.exe to run an automatic deployment of the software of our system.
The command (TrueImageCmd.exe /deploy ...) is run from a WinPE 2.0 environment on a USB drive.
The issue is that at first run (from when the PC power is off) i get the error "Failed to lock partition 1-1".
When the program fails the PC is restarted and then i repeat the exact same process and it completes successfully. Something in the initialization fails when cold start, but im not sure what and how to overcome this.
This issue reproduces on a few PC's and using several thumb drives.
Can you advice on what might be causing this? Is there a listing of error messages anywhere?

Thanks