I am getting the error: "Cannot Load Flash Programming Algorithm" on 1 PC setup, but the programmer works on a 2nd PC setup. We had issues with the programmer and had to replace IC2, IC4, IC5, IC6 to get functioning.
ARM: LPC_IAP2_512.flx
Tried to reload UVision to eliminate any corruption possibilities.
Sounds like your process could do with some sacrificial buffering hardware.
Still seems to be pointing at the PC being the issue, and what's different there.
Try alternate USB ports/cables.