I had the same problem. I did two things to make it work. first i enabled the network hotsync option in hotsync manager.

still not working, I realized that, somehow i had windows firewall on (thought i had it off) I went into the firewall settings and realized the hotsync manager wasn't selected as an expection. i selected it, now my hotsync works.

I really need the calander though, that is one of the key needs. any help on sync for calander would be much appreciated.