IEInternals

I’ve previously mentioned one site that wasn’t working properly due to sending a malformed Content-Type header. Today, I encountered another site with a similar problem, but in a subtly different way. Looking at the IE9 F12 Network tab, you...

Every few months, a Microsoft employee will send me an email complaining that Internet Explorer showed them the following dialog: This page is accessing information that is not under its control. This poses a security risk. Do you want to continue...

Thanks to TuxExplorer for reminding me to blog about this. Both Windows Explorer and Internet Explorer are able to load extensions known as Browser Helper Objects (BHOs). BHOs are a minimal extensibility point into both the shell and the browser, allowing...

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...

An amusing April Fool’s satire I ran across yesterday reminded me of a Connect bug that was reported back in the IE9 Beta. The HTML <video> control’s default context menu includes a “Save Video As…” menu option that...

Recently, a user sent in the following screenshot of a security warning they encountered when attempting to download the Microsoft Zune software: Obviously, we immediately attempted to reproduce the reported problem, and we found we were unable...

In today’s post, I’ll provide a high-level overview of features in Internet Explorer that impact the loading of ActiveX controls. Internet Explorer 6 and later allow the user to enable or disable ActiveX controls on an individual basis...

I recently encountered a blog that isn’t looking right in IE9: The site renders just fine in other browsers, and when the page is put into Compatibility View by ticking the icon in the address bar: What’s going on here...

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...

Back in the summer of 2009, I blogged about Windows 7’s new support for TLS 1.1 and TLS 1.2 . These new protocols are disabled by default, but can be enabled using Group Policy or the Advanced Tab of the Internet Control Panel: Some...

Recently, a colleague sent me an email which provided a flashback into my own past: Hey, Eric-- Why do we show this when opening HTML locally? What are we protecting the user from? -Ben I myself had sent an email with almost...

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...

This is the third and last post in the Minor Changes series; it covers changes in the final Release-to-Web (RTW) version of Internet Explorer 9. IE9 Beta Minor Changes List IE9 Release Candidate (RC) Minor Changes List The Release Candidate...

On Windows Vista and above, Internet Explorer’s Temporary Internet Files are maintained in two isolated WinINET cache containers. One cache is used for sites loaded in Protected Mode (Internet Zone and Restricted Zone) and the other cache is used...

Inside your Temporary Internet Files folder you likely have a file named msimgsiz.dat . If you open this file, you’ll find that it contains nothing but binary goo: Over the years, many people have asked or speculated about what this file is...

A few weeks ago , I discussed one compatibility issue we’d found when running a new HTML5 game . The game’s developers quickly fixed their site to return a proper character set declaration and we were able to get the game running in IE9. However...

Over the last few years, we’ve had a few questions about WinINET’s limits for file upload and download. I’ve summarized those limits in the following table: Upload (total size) Download (per file)...

Note: I mentioned this problem before ( Troubleshooting Login Cookies #3 ) but it was buried in a long post and this is an issue that lots of folks inside Microsoft hit, so I’m pulling it out into its own post. The Problem From time to time...

Earlier in IE9 , we tried to change the WinINET networking component to reject as incomplete any HTTP responses for which the Content-Length header specified more bytes than the server actually sent back. It turns out that some sites and applications...

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...

Recently, during site-compatibility testing of IE9, we encountered a cool online game that does not load properly in Internet Explorer. Using the F12 Developer Tools’ Script debugger, the page immediately hits a script error (“ c00ce56e ”...

The WinINET API allows the caller to specify the accepted MIME types for a given HTTP request by passing a null-terminated array of null-terminated strings using the lplpszAcceptTypes parameter. When calling the HttpOpenRequest API, applications must...

The IE team has been working our way through the remaining issues reported from internal and external testing of the IE9 Release Candidate. In the course of investigating one recent internal-site compatibility bug, I ran across an interesting interoperability...

On Windows 7, Internet Explorer 9 can often be installed without rebooting the system. In cases where a system restart is required, either the system lacks one of the required prerequisites (so IE Setup is forced to install it and reboot) or a running...

I recently heard from some users who are seeing lower-than-expected scores on the Speed Reading and FishIE Tank benchmarks. I went to check these tests myself and found that my laptop’s score was low. In fact, it was much lower than I’d seen...