> Debugger entered--Lisp error: (void-function diary-anniversary) There is a universal solution to this problem
M-x load-library RET diary TAB and choose which of the options make most sense or try each one of them in turn. Note that in the above load-library you are using "diary" because it is the "prefix" of function (or variable) which reported as void. The load-library call unvoids the void things.
