+3  A: 

Check the documentation for the INTERNET_CACHE_ENTRY_INFOA, especially the part that describes the CacheEntryType:

A bitmask indicating the type of cache entry and its properties. The cache entry types include: history entries (URLHISTORY_CACHE_ENTRY), cookie entries (COOKIE_CACHE_ENTRY), and normal cached content (NORMAL_CACHE_ENTRY).

This member can be zero or more of the following property flags, and cache type flags listed below.

Below that you get a list of entry types, one is

COOKIE_CACHE_ENTRY

That seems to be what you want to check before you throw everything away?

Benjamin Podszun
I ended up doing it by command line due to time restraints, but your post got me on the track nonetheless. Thanks!
Helgi Hrafn Gunnarsson