Yahoo email: If the Service Book is present on your BB, you can always delete it from that same location, and re-add it from the BIS website. Pull you battery to reboot.
For the calendar synch problem, read this at the bottom of the link: I am getting errors when I try to sync my BB with Desktop Manager - BlackBerryFAQ
I have read, also, of another issue on the calendar sync involving the range of entries for your calendar (i.e., to wide or too many). I believe I read that at the BlackBerry
site, under the common issues. You will probably find it there. That is all I know to tell you about the calendar sync issue.