I'm using a Treo 600, I sync to a work PC using Palm v4.1. I also sync to my iMac, using The Missing Sync (latest version as of May 200. Since I sync'd to my iMac last week I haven't been able to completely sync to my PC. The error I get is

OK Date Book
Conduit 'To Do List' Error: Unknown error. (FFFF)
Conduit 'Memo Pad' Error: Unknown error (FFFF)
HotSync Error: Unknown error. (FFFF)

I think the issue is in the datebook, but it appears to be sync'ing ok. My contacts are not sync'ing at all.

Why don't you try disabling the datebook, and/or some of the other conduits? In the Windows version, you click on the buddon on the traybar, then click custom.

Try playing around with that and see what happens.

- 2 Bunny