IEInternals

Over on the Microsoft Answers forum , some folks have reported that Internet Explorer doesn’t remember their login details. This is a tricky problem to troubleshoot because there are a number of different problems which get lumped together under...

From time to time, folks ask a variety of questions about 64bit IE. I hope to answer the most common questions here. NEW : Internet Explorer 10 uses x64 in a fundamentally different way than IE7, IE8, and IE9, the versions for which the post below...

Update: IE9 includes improved handling of Mixed Content. Click to learn more... Background As we developed Internet Explorer 8, we spent quite a bit of time pondering what to do about IE7’s infamous “Mixed Content” warning prompt...

Update : Internet Explorer 10 now supports CORS using XMLHTTPRequest . In Internet Explorer 8, the XDomainRequest object was introduced. This object allows AJAX applications to make safe cross-origin requests directly by ensuring that HTTP Responses...

Last week, Andy Zeigler announced the introduction of Enhanced Protected Mode (EPM) over on the IEBlog. In today’s post, I’d like to provide further technical details about EPM to help security researchers, IT professionals, enthusiasts, and...

Over the five years I’ve worked on Internet Explorer, I’ve probably seen more questions from the community about HTTP cookies than on any other topic. Cookies are an integral component of most websites in use today, and hence problems or unexpected...

Earlier today, I was asked to troubleshoot a secure site where file downloads were always failing . Having seen this problem many times often over the years, I immediately suspected that the web developer wasn’t aware that if a user tries...

If you want to remove Internet Explorer 9 beta from your computer and go back to your older version of IE, you can do so by simply following these steps.

All joking aside, last fall, I wrote about the variety of reasons why Internet Explorer might not offer to remember your password on a web form. As I mentioned then, you will not be re-prompted to save your password if you’ve previously declined...

Back in January of 2009, I announced IE8’s support for a new header-specified directive: X-Frame-Options , that can be used to mitigate ClickJacking attacks. As a declarative security measure , X-Frame-Options has minimal compatibility impact, but...

To ensure optimal performance and reliability when rendering pages, you should order the elements within the HEAD element carefully. First, I’ll explain the optimal order, and then explain the reasoning for this structure. Optimal Head Ordering...

All bugs mentioned in this post are now fixed . Internet Explorer has a number of features designed to render pages more quickly. One of these features is called the "Lookahead Downloader" and it's used to quickly scan the page as it comes in, looking...

As we explore network performance on the “real-world web”, one bad pattern in particular keeps recurring, and it’s not something that our many IE9 Networking Performance Improvements alone will resolve. The bad pattern is the use...

In general, IE8 is a significantly faster browser than prior versions. We made a number of major investments throughout the browser’s code to help ensure that IE users will have a great real-world experience on the web. However, it is definitely the...

From time-to-time, I get questions about Internet Explorer’s behavior when it comes to caching of HTTPS-delivered content. It comes as a surprise to many that by-default, all versions of Internet Explorer will cache HTTPS content so long as the...

Recently, there’s been some interest in how clients perform Certificate Revocation checks and browsers behave in the event that a revocation check cannot be completed. In today’s post, I’ll explain Internet Explorer’s default behavior...

KB 262161 outlines the maximum number of stylesheets and rules supported by Internet Explorer 6 to 9. A sheet may contain up to 4095 rules A sheet may @import up to 31 sheets @import nesting supports up to 4 levels deep Some folks have...

Internet Explorer has an Advanced option named Do not save encrypted pages to disk . By default, this option is unchecked (except for Windows Server systems) and I recommend you leave it that way. In IE9, this option does exactly what it says...

In today’s post, I’ll be discussing the use of Authenticode to sign software programs; this post will be of interest primarily to software developers. Large software companies (like Microsoft) often have an entire team dedicated to the code...

By default, IE9 will show 2 rows of your favorite sites on the about:tabs homepage. However, you can customize IE9 to show up to 5 rows with a simple registry modification. Inside the NewTabPage registry key, create a REG_DWORD named NumRows...

The HTTPS protocol allows a secure server to request that the client verify their identity with a client certificate during the initial secure handshake. By presenting a client certificate, the browser helps further defeat man-in-the-middle attacks and...

In every release of the browser, we make many major feature investments, most of which you can read about in posts over on the IEBlog . However, we also make thousands of small improvements that are often overlooked or not broadly recognized. In this...

Despite being one of the crucial security features of modern browsers, Data Execution Prevention / No Execute (DEP/NX) is not well understood by most users, even technical experts without a security background. In this post, I’ll try to provide...

Tuesday’s Update for Internet Explorer updates the IE9 Help > About dialog’s version number to v9.0.2. The update includes a number of security and functionality fixes; many of these fixes are described in the More Information section of...

As I mentioned last month , .NET Framework XAML Browser Applications ( XBAPs ) are now prevented from loading from the Internet Zone in IE9. When visiting an Internet site that utilizes an XBAP , an error message is shown, indicating that the application...