Because Microsoft's ActiveSync 4.5 will not work on machines with Windows XP (SP3), from what I've read I need to install ActiveSync 4.1. Has anyone tested this on ArcPad 10.0.2?
ArcPad 10.1 requires ActiveSync 4.5
ActiveSync 4.5 on Windows SP3 requires you to upgrade the original installer to Windows installer 4.5
Note: Make sure your Firewall is switched off during install.
ArcPadTeam blog has helpful information (not sure why this content is not on the main ESRI site) http://arcpadteam.blogspot.com/2010/10/latest-versions-of-software-firmware.html