Solved the problem - partially - with a fix posted on the Microsoft website for Office 2011 for Mac. Basically, it involved getting into the Library, which is normally invisible in Mavericks. Holding down the Option key while clicking on the "Go" menu when in the Finder makes "Library" visble as a destination.
In Library> Application Support > Microsoft move the Office folder to the desktop and rename it "Old Office".
In Library>Preferences move all the com.microsoft....plist preference files to the trash.
In Documents>Microsoft move the Office 2011 Identities folder to the desktop and rename it "Old Office 2011 identities".
Then restart in safe mode by holding down the Shift key while restarting to check if Office works. In my case, both Word and Excel opened. I had to accept the identities on the first open, but they were already filled in. Also in safe mode my display preferences were not accessible, so I did not have my preferred resoltuion. However, a regular restart - while Excel and WOrd were open brought back the display preferences and Word and Excel both opened and performed nomrally. The library files I had moved to the desktop or trash had been recreated, so they could then be trashed and emptied.
I said this partially solved the problem because if I shut down and restarted, or simply restarted, Office again "encountered a problem" and crashed. So I had to go through the procedure all over again. But until Apple and/or Microsoft solves the conflict problem, at least I can get Office 2011 to work.
Incidentally, installing the latest Microsoft updates was not an option. They latest updates were already installed when I switched to Mavericks; and there have been no new ones since.
