diary-from-outlook-function is a variable defined in `diary-lib.el'.
Its value is

  • This variable may be risky if used as a file-local variable.

If non-nil, a function of one argument for `diary-from-outlook' to call.
If the current buffer contains an Outlook-style appointment message,
this function should extract it into a diary entry. If the argument is
nil, it should ask for confirmation before adding this entry to the diary.
For examples, see `diary-from-outlook-rmail' and `diary-from-outlook-gnus'.