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Change the Internet Explorer User Agent String (All Windows) Popular

Whenever a web browser is used to connect to a remote web server it includes a User Agent string that contains details about browser and operating system. This tweak allows you to add or remove additional information from this string.

This tweak can be easily applied using WinGuides Tweak Manager.
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A standard user agent string would look similar to:

Mozilla/4.0 (compatible; MSIE 5.5; Windows NT 5.0)

Which means Internet Explorer 5.5 running on Windows 2000.

Changing the Default User Agent Values
Open your registry and find the key below. If it does not already exist then create it.

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\5.0\User Agent]

Create three new string values called "Compatible", "Version" and "Platform". Set them to equal what you would like to be displayed instead of "compatible", "MSIE 5.5" and "Windows NT 5.0" respectively in the example above.

You can also modify the value of "(Default)" to change the browser name "Mozilla/4.0" in the example above.

Changing the Branded User Agent String
In addition when a customized user agent string is used it may contain additional information set by the company that created a branded version of the browser. For example a branded version from an ISP may look like:

Mozilla/4.0 (compatible; MSIE 5.5; Windows NT 5.0; Your_ISP_Name)

Since this information is sent to the remote web server it may be stored in the web server log files and therefore possibly used to track branded versions of a web browser.

To change it open your registry and find the key [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\User Agent\Post Platform].

Each value name listed in this key will be sent to the remote web server as an additional entry in the user agent string. To remove any additional information delete the values within the [Post Platform] key. To add additional entries create a string value and name it the string you want to be sent.

Restart Internet Explorer for the changes to take effect.

Note: This tweak may affect some online services that read this information to detect the operating system such as Microsoft Windows Update.

Registry Editor Example
|VersionREG_SZMSIE 5.5|
|PlatformREG_SZWindows NT 5.0 |
Registry Settings
System Key: [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\
Internet Settings\5.0\User Agent]
Value Name: (Default), Compatible, Version, Platform
Data Type: REG_SZ (String Value)

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Disclaimer: Modifying the registry can cause serious problems that may require you to reinstall your operating system. We cannot guarantee that problems resulting from modifications to the registry can be solved. Use the information provided at your own risk.

Last modified: August 15, 2003