Continuing the discussion in the previous post, offcourse index.dat is not a secret record of any kind, but well ..anything in the world could be misused ..didn't you hear the news wife jailed for knife attack does that mean we should not use kitchen knife at all ??
The index.dat file functions as an active database, which runs as long as Windows is active. It functions as a repository of redundant information, such as web URLs, search queries, and recently opened files. Its role is similar to that of an index file in the field of databases, where a technique called "indexing" stores the contents of a database in a different order to help speed up query responses. Similarly, when the Autocomplete function is enabled in Internet Explorer, every web address visited is sorted in the index.dat file, allowing the Internet Explorer to attempt to find an appropriate match when a user types in an edit field.
The files were not deleted for the same reason users have trouble deleting them—other processes kept them open. Wininet tried to delete them, but frequently couldn’t do it normally because another application (like office) is actively using the cached file. we do keep a list of things we couldn’t delete and occasionally go back and try to delete them.
Yeah, right !they are accessible to any apps, but so is the file system. And the network stack that sends and receives http requests.I agree with the feedback that in the past when you cleared the cache, wininet just marked the entries as deleted instead of actually erasing them but the bar in IE 7 has been raised quite significantly have a look at Clear my Tracks: yes please!!!!
Need to know more about index.dat ? Jeff talks about it (although he needs no introduction but for the record he is Software Design Engineer in Browser UI Team @ Microsoft)
Some more great information about index.dat .. Windows Network Development Team