HPC Explorer does not support XP. You are going to have to install the CE 2.0 rom chip into you A-11. Strange but true. HPC Explorer does not support CE 2.0 but an easy way to go is to install ActiveSync 3.8
(the last ActiveSync to support CE 2.0
).
If you want to stick to CE 1.0, buy a Compact Flash card of reasonable size ... I use a 4MB card for CAB setup transfer purposes. If your PC has no CF slot in it, get a card reader for the PC.
Hope this cracks the problems.