Just in case anyone else is having problems with Activesync - here is
what worked for me.

The symptom: My Activesync got stuck at "Retrieving Settings" (WinXP
with PPC Mobile 5.0, Activesync 4.5.0 beta).

After trying opening ports on the firewall (Sygate), disabling the
firewall entirely, reinstalling various versions of Activesync, giving
up in disgust for a couple of weeks, I've finally got activesync to work :-

The cure:
Edit the PPC registry (using say PHM Registry Editor, from
http://www.phm.lu/Products/PocketPC/RegEdit/ ) as follows:-

Reg Sub Key: [HKEY_LOCAL_MACHINE\Drivers\USB\FunctionDrivers\RND IS]
Name of value to add: MTU
Type: DWORD
Data: 1514 (decimal)

Reg Sub Key: [HKEY_LOCAL_MACHINE\Drivers\USB\FunctionDrivers\RND IS]
Name of Value to add: MaxOutTransfer
Type: DWORD
Data: 1642 (decimal)

***Edit the registry at your own risk, backup first.... Don't run with
scissors, etc...

This came from google(activesync retrieving settings), which pointed at
http://www.aximsite.com/boards/showthread.php?t=130288

Hope this helps anyone else having the same problem.