"...an error occurred while sending data from the iPhone" - caused by latest iPhone update today?

I've been syncing my iPhone to my (non-apple) desktop for several months without difficulty.

Today I accepted the latest upgrade to my iPhone software.

Since it installed, it will not sync.

It gives the error message "iTunes could not sync calendars to the iPhone "Steve's iPhone" because an error occurred while sending data from the iPhone." After rebooting the desktop, the error repeats, and it's now in hour 2 of the continuing message "Syncing Steve's iPhone (Step 2 of 2) - Finishing sync"

Has anyone else run into this Undocumented Feature of the latest upgrade?

As bugs go, this is pretty serious for those of us who depend on syncing the iPhone and desktop for our business!

Thanks to anyone who can help!

Steve Callender