Index.dat files are used by 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 Internet Explorer and Windows use them all the time.
Where are located Index.dat files?
Location of index.dat files depends on the version of Windows and whether or not you are using user 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 Windows Explorer 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
If you have Windows XP or Windows 2000 then index.dat files are in these locations (note that on your PC they can be on other drive instead of drive C:
C:Documents and SettingsCookiesindex.dat
C:Documents and SettingsLocal SettingsHistoryHistory.IE5index.dat
C:Documents and SettingsLocal SettingsHistoryHistory.IE5
MSHistXXXXXXXXXXXindex.dat
What is in Index.dat files?
As already mentioned, index.dat files are binary files. Their content 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. The next important thing in the header are the names of the four subfolders in which are located the cached files from the Internet (they are not in the header when the index.dat file is for cookies and history but UserData index.dat files also have such subfolders).
How to erase or clean Index.dat files?
Erasing or cleaning of the index.dat files is not an easy task because they are opened by Internet Explorer and Windows 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). However 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 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.
Delete Index Dat Files
1. What are index .dat files?
When you visit a webpage, the content (html files, pictures, flash, java scripts and other) is downloaded and saved to your computer. This is called the cache or Temporary Internet Files. Every time a cache entry is saved, it will also insert a pointer to the cache files in the index.dat file. Internet Explorer uses Index.dat files to keep track of offline data (the cache) like an index in the end of the book.
a. History index.dat files
This is actually a collection of index.dat files. These are history indices, every time you visit a homepage, that address will be inserted into to history index.dat files. Each history index.dat file is associated with a date. In the browser, this is what the history shows.
b. Cache index.dat file
Internet Explorer uses the cache for two reasons. The primary reason is for fast access to web pages. If the web page you visit hasn't changed since the last time you visited, Internet Explorer will load the homepage from the hard drive (the cache) instead of the web. To find the cached homepage on the hard drive, it searches in the index.dat file and the browser shows the local page. The cache will also allow users to access homepages offline.
c. Cookies index.dat file
Every time a web site creates a cookie on your machine, IE will insert an entry in the cookies index.dat file that associates the homepage with the cookie file. Next time you visit that homepage, IE finds the cookie file through the index.dat file.
2. Why are index.dat files a privacy threat?
Index.dat files contain url's to every web site you have visited since the installation of your Operating System. It also contains links to every picture and other Internet resource you have accessed. Index.dat files are in plain text and can be read by anyone capable of opening a file in Notepad. But this is not enough, index.dat file can't be removed manually easily. If you select it in Explorer and hit the delete button you will get an error message that it's being used. In other words, on your hard drive, there are plain text files called index.dat, they contains links to every web resource you have ever visited and you are not able to erase this file. Perhaps no further explanation is needed of why these files are a privacy threat?
3. Index.dat files location
These files are located under each user profile in three different locations. To be able to see them in Windows Explorer make sure you have enabled it to view hidden and system files.
a. The location of the history index.dat files
It is located in the following folder: ?C:Documents and SettingsLocal SettingsHistoryHistory.IE5?
Also the file is present in a number of subdirectories with the prefix MSHist, (for example: ?C:Documents and SettingsLocal SettingsHistoryHistory.IE5MSHist012004073120040801?)
You can find it by typing this address in the Explorer address field and replacing '' with a valid username.
b. The location of cache index.dat file
It is located in the following folder:
?C:Documents and SettingsLocal SettingsTemporary Internet FilesContent.IE5?.
You can find it by typing this address in the Explorer address field and replacing '' with a valid username.
c. The location of the cookie index.dat file
This file is the easiest to find and is found here 'C:Documents and SettingsCookies'.
You can find it by typing this address in the Explorer address field and replacing '' with a valid username.
4. How do I erase index.dat files?
Erasing the index.dat files is a complicated and time consuming task. The files are locked by the system and can't be erased directly.
On Windows 95/98/ME you need MS-DOS skills. The idea is to create a boot disk, start the computer with the boot disk, and remove the files from the MS-DOS prompt.
On Windows NT/2000/XP/2003 you can make the Windows unlock the files by creating a new temporary user with administrator rights.
4.1 The easy way to delete index.dat files
Instead of using boot disks and other methods, try out Wipe Expert, and let it delete the index.dat files or optionally clean it. Our product will also clean up many other privacy threats in your system.
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