Some Activesync 4.1 users have reported an error as soon as the Windows Mobile 5 device is cradled: : “Activesync Connection Manager has encountered a problem and needs to close”

This happens if Winsock is corrupted on the computer

To resolve this, first reset the winsock using KB811259

The “netsh winsock reset” command on Windows XP SP2 does not work as expected, so you are better off resetting winsock manually using the KB article.

After resetting winsock, restart the computer and then try synching.