How to Install and Use Compatibility Mode in Internet Explorer 5

ID: Q197311

The information in this article applies to:

SUMMARY

This article describes how to install and use Compatibility mode with Internet Explorer 5. You can use Compatibility mode to run an Internet Explorer 4-compatible browser "side-by-side" with Internet Explorer 5.

The following topics are discussed:

MORE INFORMATION

Purpose of Compatibility Mode

Some Web content can be affected by changes to the HTML parsing engine or object (scripting) model incorporated into new versions of Internet Explorer. For this reason, Web page authors or developers need to test their content with each version of Internet Explorer for which their content is designed. Prior to Internet Explorer 5, testing Web site compatibility with various versions of Internet Explorer required multiple computers or dual-boot configurations. With Compatibility mode, you can run an Internet Explorer 4-compatible browser side-by-side with Internet Explorer 5. Compatibility mode is designed for testing HTML parsing and script issues and is not intended to be used as a primary Web browser.

How to Download or Install Compatibility Mode

To download or install Compatibility mode, use the following steps:

1. Start the Internet Explorer 5 Setup program, click I Accept The

   Agreement, click Next, click Customize Your Installation, and then
   click Next.

2. In the Components Options dialog box, click Advanced, and then click to
   select the Compatibility check box. If you want to download (instead of
   install) Compatibility mode, click to select the Download Only check
   box.

3. Click OK, and then click Next to continue the Setup program.

NOTE: If you are not running Internet Explorer 4 when you follow the above steps, you cannot select the Compatibility option. You can download or install Compatibility mode only when you upgrade or downloade from Internet Explorer 4. Compatibility mode is not supported for versions of Internet Explorer prior to 4.0. If you are already running Internet Explorer 5 and you need to download or install Compatibility Mode, uninstall Internet Explorer 5 before following the above steps. For information about uninstalling Internet Explorer 5, see the following article in the Microsoft Knowledge Base:

   ARTICLE-ID: Q193934
   TITLE     : How to Uninstall Internet Explorer 5 Beta

How to Use Compatibility Mode

To use Internet Explorer 4 to browse the Internet after installing Internet Explorer 5, click Start, point to Programs, point to Internet Explorer, and then click "Previous Internet Explorer Ver. 4."

NOTE: When you install Internet Explorer 5 with the Compatibility option, Internet Explorer 5 and Internet Explorer 4 share the same Internet options. You may not be able to change all settings for the browser while using this mode. When you are using Compatibility mode, you should change Internet options through Control Panel, not by clicking Internet Options on the View menu in Internet Explorer.

How to Identify Compatibility Mode

To determine if you are using the Compatibility-mode browser, use the following steps:

1. In Internet Explorer, click About Internet Explorer on the Help menu.

2. If the version is reported as "Side-by-Side Mode," you are using

   Compatibility mode.

NOTE: Compatibility mode can be identified by Web developers using the "compat" string, which is added to the User Agent for the Compatibility- mode browser. For example, the User Agent for Compatibility mode in Windows 98 is:

   Mozilla/4.0 (compatible; MSIE 4.01; Windows 98; compat)

Additional query words:
Keywords          : kbsetup msiew95 msient msiew98 
Platform          : WINDOWS
Issue type        : kbhowto

Last Reviewed: March 19, 1999