"Index.dat" files are used by web browser like Internet Explorer and Windows to store history, Internet cache, cookies, UserData records and other information about what you have done in Internet or in your PC. Although some of their functions are useful, they are dangerous privacy threat - any person with even little knowledge about index.dat files locations and structure can see history of almost all of your computer activities. Index.dat files are not the only privacy threat but they are the most obscure and dangerous one because they are hard to find and even harder to delete. In fact, in most cases it is impossible to delete "Index.dat" files manually because web browser and Windows use them all the time. Location of "index.dat" files depends on the version of Windows OS and whether or not you are using peoples profiles. Regardless of Windows version in many cases you can't see or find "index.dat" file using Windows Explorer. There is a little file called desktop.ini in each directory where index.dat file is located. This desktop.ini file forces web browser to hide index.dat files and to show the contents of Internet cache or history instead. However you can use some other file utility and binary (hex) editor to find the files and read their content. If you have Windows Me, Windows 98, Windows NT or Windows 95 then "index.dat" files are in these locations: C:WindowsCookiesindex.dat C:WindowsHistoryindex.dat C:WindowsHistoryMSHistXXXXXXXXXXXXXXXXXXindex.dat (XXXX are some digits) C:WindowsHistoryHistory.IE5index.dat The content of "index.dat" can be seen only with binary (hex) editor. We will examine an "index.dat" file from the Internet cache(Temporary Internet Files). Actually the "index.dat" header is much larger but this is the most important part of it. The first thing is the version of the "index.dat" file (Client UrlCache MMF Ver 4.7) - this particular file is from Internet Explorer version 4 but the "index.dat" file format is very similar in Internet Explorer 5.x and 6. Erasing or cleaning of the "index.dat" files is not an easy task because they are opened by Internet Explorer and Windows OS all the time. If you are using Windows Me, Windows 98 or Windows 95 you can restart in DOS mode and then you can delete index.dat files one by one (look in the folders that are mentioned above). If you are using Windows XP, Windows 2000 or Windows NT this won't work. Mil Shield is a powerful privacy protection program that was designed specifically to clean and shred the "index.dat" files content. Unlike the other methods of dealing with "index.dat" file content, shredding is the best because it doesn't destroy the entire structure of the "index.dat" file which can cause Internet Explorer or Windows to crash but instead cleans and shreds only the privacy threatening URL, LEAK and REDR records. Additional benefit is the ability to preserve the tracks from some chosen by you sites (selective cleaning), which makes your web browsing more comfortable and safe (it is rather suspicious to always have empty history, cookies and cache - it is better to leave some tracks from "innocent" sites). Mil Shield also cleans all other tracks as cookies, history, cache, AutoComplete records, UserData records, history of recently used folders and documents and many other