Has anyone seen this error before and know the remedy?

Now Contact synchronization failed
“Now Contact” failed (error = #-19986)

I can sync existing changed records and new records from Treo to Desktop. But not Desktop to Treo.

Also if I change a Conduit setting, when I quit HotSync Manager it crashes

NUTD 5.3.2
OSX 10.5.6
Treo 755p