Duplicate calendar events in Outlook 2011
If your Outlook client is not crashing when you select calendars, there is a method in the UI to remove blocks of duplicate or outdated events. I can't find the link to give credit, but here is the process:


create a new calendar categorization, call it 'delete' or something.
go to calendars view, in list view not grid.
Cmd-Shift-F 'Advanced Find'
Select 'All Events' button
Select search option 'Date Created' = 'Any Date', or use the criteria to identify your targeted events. Select contiguous blocks by clicking one, and Shift-Click another.
Apply your 'delete' categorization via drag/drop or right-click select 'delete'
Select File/Export...


Outlook for Mac Data File
Items in the category: 'delete'
Next
'Yes, delete items after they are exported'
uncheck the box because you definitely want to delete all items in this category.

Finish


The genius of this method is it avoids the disastrous 'prompt for delete for each event' cycle.

Sorry its not a script, I would prefer that as well but I could not find one.