Temporary Internet Files
Encyclopedia
Temporary Internet Files is a folder on Microsoft Windows
which holds browser caches. The directory is used by Internet Explorer
and other web browser
s to cache pages and other multimedia content, such as video and audio files, from websites visited by the user. This allows such websites to load more quickly the next time they are visited. Not only web browsers access the directory to read or write, but also Windows Explorer
and Windows Desktop Search.
, image
s, Cascading Style Sheets
and JavaScript scripts
) are saved to the Temporary Internet Files folder, creating a cache
of the web page on the local computer's hard disk, or other form of digital data storage. The next time the user visits the cached website, only changed content needs to be downloaded from the Internet; the unchanged data is available in the cache.
Despite the name 'temporary', the cache of a website remains stored on the hard disk until the user manually clears the cache. This is often regarded as a privacy issue http://www.milincorporated.com/a-temporary-internet-files.html http://www.pchell.com/support/privacy.shtml, because anyone with access to the computer can view the cache. The contents of the folder are indexed using an index.dat
file, a form of database.
The Temporary Internet Files cache can be useful in certain situations. For example, if no Internet connection is available, previously cached websites are still available offline. Certain online media files (such as embedded Flash movies) are not easily accessed directly through Internet Explorer, but are automatically saved into the cache after viewing them. Depending on the type of website and how often it is updated, the cached data may not reflect the online version of the website. The cache is also useful for police to collect forensic evidence
.
The cache can be cleared by using Internet Options within the Internet Explorer interface, but this method is subject to deletion privacy issues. Many alternative tools exist to erase
the data instead.
, the cache is usually located at %USERPROFILE%\Local Settings\Temporary Internet Files (where %USERPROFILE% is an environment variable
pointing to the root directory of the logged-in user's user profile
). However, the cache may be moved by changing a value in the registry. Occasionally an additional (hidden) cache named "Temporary Internet Files" may appear in %USERPROFILE%\Local Settings\Temp\Temporary Internet Files or in %USERPROFILE%\Local Settings\Temporary Internet Files. This location can only be deleted by manually accessing the folder and removing it.
One scenario that often (albeit not always) leads to the occurrence of this phenomenon proceeds as follows:
The only known way to release the lock on the aforementioned files is to reboot the OS. One can also kill the offending instance of svchost.exe, thus releasing the lock, but this normally renders the machine unusable, since it also terminates all the services hosted by the same instance of svchost.exe.
Also, the Windows Webclient (MRxDAV) is, however, known to create temporary copies of downloaded files under C:\Documents and settings\LocalService\Temp\Temporary Internet Files\Content.IE5.
, the cache for Internet Explorer 7
is usually located at %LOCALAPPDATA%\Microsoft\Windows\Temporary Internet Files\Low\Content.IE5 where %LOCALAPPDATA% is an environment variable pointing to %USERPROFILE%\AppData\Local (note that the checkbox for 'Hide protected operating system files
' under 'Folder Options' must be unchecked and the 'Show hidden files and folders' option enabled for the files to be visible in Windows Explorer
). For all other Trident
-based applications, the cache is located at %LOCALAPPDATA%\Microsoft\Windows\Temporary Internet Files. Like on Windows XP, the location of the cache can be changed by moving the folder location in Internet Explorer or by changing a value in the registry.
Microsoft Windows
Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
which holds browser caches. The directory is used by Internet Explorer
Internet Explorer
Windows Internet Explorer is a series of graphical web browsers developed by Microsoft and included as part of the Microsoft Windows line of operating systems, starting in 1995. It was first released as part of the add-on package Plus! for Windows 95 that year...
and other web browser
Web browser
A web browser is a software application for retrieving, presenting, and traversing information resources on the World Wide Web. An information resource is identified by a Uniform Resource Identifier and may be a web page, image, video, or other piece of content...
s to cache pages and other multimedia content, such as video and audio files, from websites visited by the user. This allows such websites to load more quickly the next time they are visited. Not only web browsers access the directory to read or write, but also Windows Explorer
Windows Explorer
This article is about the Windows file system browser. For the similarly named web browser, see Internet ExplorerWindows Explorer is a file manager application that is included with releases of the Microsoft Windows operating system from Windows 95 onwards. It provides a graphical user interface...
and Windows Desktop Search.
Overview
Each time a user visits a website using Microsoft Internet Explorer, files downloaded with each web page (including htmlHTML
HyperText Markup Language is the predominant markup language for web pages. HTML elements are the basic building-blocks of webpages....
, image
Image
An image is an artifact, for example a two-dimensional picture, that has a similar appearance to some subject—usually a physical object or a person.-Characteristics:...
s, Cascading Style Sheets
Cascading Style Sheets
Cascading Style Sheets is a style sheet language used to describe the presentation semantics of a document written in a markup language...
and JavaScript scripts
JavaScript
JavaScript is a prototype-based scripting language that is dynamic, weakly typed and has first-class functions. It is a multi-paradigm language, supporting object-oriented, imperative, and functional programming styles....
) are saved to the Temporary Internet Files folder, creating a cache
Cache
In computer engineering, a cache is a component that transparently stores data so that future requests for that data can be served faster. The data that is stored within a cache might be values that have been computed earlier or duplicates of original values that are stored elsewhere...
of the web page on the local computer's hard disk, or other form of digital data storage. The next time the user visits the cached website, only changed content needs to be downloaded from the Internet; the unchanged data is available in the cache.
Despite the name 'temporary', the cache of a website remains stored on the hard disk until the user manually clears the cache. This is often regarded as a privacy issue http://www.milincorporated.com/a-temporary-internet-files.html http://www.pchell.com/support/privacy.shtml, because anyone with access to the computer can view the cache. The contents of the folder are indexed using an index.dat
Index.dat
In the Microsoft Windows operating system, index.dat is a database file used by the Internet Explorer web browser. It is used to improve performance.-Function:...
file, a form of database.
The Temporary Internet Files cache can be useful in certain situations. For example, if no Internet connection is available, previously cached websites are still available offline. Certain online media files (such as embedded Flash movies) are not easily accessed directly through Internet Explorer, but are automatically saved into the cache after viewing them. Depending on the type of website and how often it is updated, the cached data may not reflect the online version of the website. The cache is also useful for police to collect forensic evidence
Forensic identification
Forensic identification is the application of forensic science, or "forensics", and technology to identify specific objects from the trace evidence they leave, often at a crime scene or the scene of an accident. Forensic means "for the courts"....
.
The cache can be cleared by using Internet Options within the Internet Explorer interface, but this method is subject to deletion privacy issues. Many alternative tools exist to erase
Data erasure
Data erasure is a software-based method of overwriting data that completely destroys all electronic data residing on a hard disk drive or other digital media. Permanent data erasure goes beyond basic file deletion commands, which only remove direct pointers to data disk sectors and make data...
the data instead.
Windows XP
On Windows XPWindows XP
Windows XP is an operating system produced by Microsoft for use on personal computers, including home and business desktops, laptops and media centers. First released to computer manufacturers on August 24, 2001, it is the second most popular version of Windows, based on installed user base...
, the cache is usually located at %USERPROFILE%\Local Settings\Temporary Internet Files (where %USERPROFILE% is an environment variable
Environment variable
Environment variables are a set of dynamic named values that can affect the way running processes will behave on a computer.They can be said in some sense to create the operating environment in which a process runs...
pointing to the root directory of the logged-in user's user profile
User profile
A user profile is a collection of personal data associated to a specific user. A profile refers therefore to the explicit digital representation of a person's identity...
). However, the cache may be moved by changing a value in the registry. Occasionally an additional (hidden) cache named "Temporary Internet Files" may appear in %USERPROFILE%\Local Settings\Temp\Temporary Internet Files or in %USERPROFILE%\Local Settings\Temporary Internet Files. This location can only be deleted by manually accessing the folder and removing it.
One scenario that often (albeit not always) leads to the occurrence of this phenomenon proceeds as follows:
- User A runs Internet Explorer from his own account, but under the credentials of user B. This is achieved by using the runasRunasIn computing, runas is a command in the Microsoft Windows line of operating systems that allows a user to run specific tools and programs under a different username to the one that was used to logon to a computer interactively...
command, e.g. runas /user:B iexplore.exe. The functionality of runas is provided and supported by Windows XP Secondary Logon service. - User A quits Internet Explorer and logs out of his account. However, due to a bug in Windows XP, the svchost.exeSvchost.exeIn the Windows NT family of operating systems, svchost.exe is a system process which hosts multiple Windows services. Its executable image, %SystemRoot%\System32\Svchost.exe or %SystemRoot%\SysWOW64\Svchost.exe runs in multiple instances, each hosting one or more services...
process that hosts the Secondary Logon service retains the ownership of critical Internet Explorer data files belonging to user B and located in B's profile directories (for example, index.dat file located in %USERPROFILE%\Local Settings\Temp\Temporary Internet Files\Content.IE5 directory). For this reason these files remain inaccessible for writing. - User B logs into his account and runs Internet Explorer. Internet Explorer is unable to obtain write access to the aforementioned files, which makes it quietly recreate the supporting directories under the current %TEMP% location as a fail-safe measure. The data from the original directories is not copied to the new ones. Internet Explorer will continue to use the directories under %TEMP% until the files at the original location become writable again.
The only known way to release the lock on the aforementioned files is to reboot the OS. One can also kill the offending instance of svchost.exe, thus releasing the lock, but this normally renders the machine unusable, since it also terminates all the services hosted by the same instance of svchost.exe.
Also, the Windows Webclient (MRxDAV) is, however, known to create temporary copies of downloaded files under C:\Documents and settings\LocalService\Temp\Temporary Internet Files\Content.IE5.
Windows Vista
On Windows VistaWindows Vista
Windows Vista is an operating system released in several variations developed by Microsoft for use on personal computers, including home and business desktops, laptops, tablet PCs, and media center PCs...
, the cache for Internet Explorer 7
Internet Explorer 7
Windows Internet Explorer 7 is a web browser released by Microsoft in October 2006. Internet Explorer 7 is part of a long line of versions of Internet Explorer and was the first major update to the browser in more than 5 years...
is usually located at %LOCALAPPDATA%\Microsoft\Windows\Temporary Internet Files\Low\Content.IE5 where %LOCALAPPDATA% is an environment variable pointing to %USERPROFILE%\AppData\Local (note that the checkbox for 'Hide protected operating system files
Attribute (computing)
In computing, an attribute is a specification that defines a property of an object, element, or file. It may also refer to or set the specific value for a given instance of such....
' under 'Folder Options' must be unchecked and the 'Show hidden files and folders' option enabled for the files to be visible in Windows Explorer
Windows Explorer
This article is about the Windows file system browser. For the similarly named web browser, see Internet ExplorerWindows Explorer is a file manager application that is included with releases of the Microsoft Windows operating system from Windows 95 onwards. It provides a graphical user interface...
). For all other Trident
Trident (layout engine)
Trident is the name of the layout engine for the Microsoft Windows version of Internet Explorer.It was first introduced with the release of Internet Explorer version 4.0 in October 1997; it has been steadily upgraded and remains in use today...
-based applications, the cache is located at %LOCALAPPDATA%\Microsoft\Windows\Temporary Internet Files. Like on Windows XP, the location of the cache can be changed by moving the folder location in Internet Explorer or by changing a value in the registry.