How to remove index.dat files?

Abstract

Index.dat files are a privacy issue. Every web site you ever visited remains in this file, even after you have removed all temporary internet files and history. Index.dat files are locked by the system and hence not possible to delete or modify. The primary purpose of this article is to explain index.dat files and how they compromise your privacy and what you can do about this.

Privacy Mantra is FREE and will clean and delete index.dat files.

Table of contents

1. What are index.dat files?
2. In what way are index.dat files a privacy threat?
3. Where are the index.dat files located?
4. How do I erase index.dat files?

1. What are index .dat files?

Every time you visit a homepage the contents (html files, pictures, flash-scripts – everything) are downloaded to your computer and saved. This is called the cache or Temporary Internet Files (TIF). 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. IE uses three different types index.dat files.

1.1 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.

1.2 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.

1.3 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. In what way are index.dat files a privacy threat?

Index.dat files contains 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. Where are the index.dat files located?

These files are located under each user profile in three different locations. The files are hidden and not easily found through Explorer. To be able to see them in Explorer make sure you have enabled Explorer to view hidden and system files.
Under Explorer->Tools->Folder Options->View enable Show Hidden Files and Folders.

3.1 The location of cache index.dat file

You will not be able to find this file by browsing through the folder view in explorer, you can find it by typing this address in the Explorer address field and replacing ‘username’ with a valid username.

C:\Documents and Settings\username\Local Settings\Temporary Internet Files\Content.IE5\

3.2 The location of the history index.dat files

You will not be able to find these files by browsing through the folder view in explorer, you can find it by typing this address in the Explorer address field and replacing ‘username’ with a valid username.

‘C:\Documents and Settings\username\Local Settings\History\History.IE5\’
and a number of subdirectories with the prefix MSHist, ‘C:\Documents and Settings\\Local Settings\History\History.IE5\MSHist012004073120040801’

3.3 The location of the cookie index.dat file

This file is the easiest to find and is found here ‘C:\Documents and Settings\username\Cookies’.

4. How do I erase index.dat files?

Erasing the index.dat files is a complicated and time consuming task. As mentioned earlier, the files are locked by the system and can’t be erased directly. To remove them in 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. Here is a step-by-step guide:

    1. 1. Create a new account at Control Panel->User Accounts->Create a new account remember to give it administrator rights and preferable a password.
      2. Log out with your current user (the one with the index.dat files you want to remove).
      3. Log in with the newly created user and locate and delete the index.dat files with Explorer.

Remember that there may be many of them!

4.1 The easy way to delete index.dat files

Privacy Mantra is FREE and can delete the index.dat files or optionally clean it. Privacy Mantra will also clean up many other privacy threats in your system.